TENB

tenb-202602040001660280false00016602802026-02-042026-02-04

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): February 4, 2026

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland, 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On February 4, 2026, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter and full year ended December 31, 2025. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 8.01    Other Events. On January 15, 2026, the Company's Board of Directors approved an increase to the Company's existing share repurchase program of up to an additional $150 million, which is also announced in the press release furnished as Exhibit 99.1 to this report. Repurchases under the share repurchase program may be made in the open market, in privately negotiated transactions or in such other manner as determined by the Company, including through repurchase plans complying with the rules and regulations of the Securities and Exchange Commission. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Fourth Quarter and Full Year 2025 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on February 4, 2026, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:February 4, 2026By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202510290001660280false00016602802025-10-292025-10-29

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): October 29, 2025

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On October 29, 2025, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended September 30, 2025. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Third Quarter 2025 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on October 29, 2025, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:October 29, 2025By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202507300001660280false00016602802025-07-302025-07-30

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): July 30, 2025

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On July 30, 2025, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended June 30, 2025. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 8.01 Other Events. On July 28, 2025, the Company's Board of Directors approved an increase to the Company's existing share repurchase program of up to an additional $250 million, which is also announced in the press release furnished as Exhibit 99.1 to this report. Repurchases under the share repurchase program may be made in the open market, in privately negotiated transactions, or in such other manner as determined by the Company, including through repurchase plans complying with the rules and regulations of the Securities and Exchange Commission. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Second Quarter 2025 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on July 30, 2025, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:July 30, 2025By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202504290001660280false00016602802025-04-292025-04-29

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): April 29, 2025

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On April 29, 2025, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended March 31, 2025. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces First Quarter 2025 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on April 29, 2025, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:April 29, 2025By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202502070001660280false00016602802025-02-072025-02-07

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): February 7, 2025

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland, 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On February 7, 2025, Tenable Holdings, Inc., a Delaware corporation (“Tenable”), issued a press release announcing the closing of the Acquisition (as defined below). In that press release, Tenable also announced certain financial guidance regarding the first quarter ended March 31, 2025 and the full year ended December 31, 2025. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by Tenable, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 8.01     Other Events. On February 7, 2025, Ermetic Ltd., a company organized under the laws of the State of Israel (“Purchaser”) and an indirect, wholly owned subsidiary of Tenable, completed its previously announced acquisition (the “Acquisition”) of Vulcan Cyber Ltd., a company organized under the laws of the State of Israel (“Vulcan Cyber”). The Acquisition was effectuated pursuant to a Share Purchase Agreement, dated as of January 29, 2025 (the “SPA”) by and among Purchaser, Vulcan Cyber, each of the shareholders of Vulcan Cyber identified in the SPA or joined to the SPA pursuant to a joinder agreement (collectively, the “Sellers”), Shareholder Representative Services LLC, a Colorado limited liability company, solely in its capacity as the representative, agent and attorney-in-fact of the indemnitors under the SPA, and Tenable, Inc., a Delaware corporation and a wholly owned subsidiary of Tenable, solely for the purposes of Section 12.2 of the SPA. Under the terms of the SPA, the Purchaser acquired all of the outstanding share capital of Vulcan Cyber from the Sellers for approximately $148 million in cash and $2 million in Tenable restricted stock units, subject to certain customary purchase price adjustments as set forth in the SPA. The foregoing description of the SPA and the Acquisition does not purport to be complete and is qualified in its entirety by reference to the SPA, which was filed as Exhibit 2.1 to Tenable’s Current Report on Form 8-K filed with the Securities and Exchange Commission on January 29, 2025 and is incorporated into this report by reference. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release, dated February 7, 2025.

101.SCHInline XBRL

tenb-202502050001660280false00016602802025-02-052025-02-05

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): February 5, 2025

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland, 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On February 5, 2025, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter and full year ended December 31, 2024. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Fourth Quarter and Full Year 2024 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on February 5, 2025, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:February 5, 2025By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202501030001660280false00016602802025-01-032025-01-03

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): January 3, 2025

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland, 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On January 4, 2025, Tenable Holdings, Inc. (the "Company") issued a press release regarding the passing of Amit Yoran, the Company’s Chief Executive Officer and Chairman, further described in Item 5.02 below. In that press release, the Company also announced that it expects to meet or exceed the financial guidance for the fourth quarter and full year ended December 31, 2024 as set forth in the Company’s earnings release dated October 30, 2024. A copy of the press release is furnished as Exhibit 99.1 to this Current Report on Form 8-K. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 5.02    Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers. On January 4, 2025, the Company announced with deep sadness that Mr. Yoran had passed away on January 3, 2025. The Company previously announced on December 5, 2024 that Mr. Yoran had begun a temporary medical leave of absence from his duties as Chief Executive Officer. At that time, the Board of Directors appointed Stephen A. Vintz, the Company’s Chief Financial Officer, and Mark Thurmond, the Company’s Chief Operating Officer, to serve as Co-Chief Executive Officers, with Mr. Vintz serving as principal executive officer, on an interim basis. On January 4, 2025, in light of Mr. Yoran’s passing, the Board of Directors determined that Mr. Vintz and Mr. Thurmond will continue to serve as interim Co-Chief Executive Officers as the Board conducts a search for the Company’s next Chief Executive Officer, which will include both internal and external candidates. Also on January 4, 2025, the Board appointed Arthur W. Coviello, Jr., the Board’s lead independent director, to serve as Chairman of the Board and decreased the size of the board to eight directors, each effective immediately. The Board of Directors, executive leadership team, and employees of Tenable extend their deepest condolences to Mr. Yoran’s family and express profound gratitude for his leadership and extraordinary contributions to the Company. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces the Passing of Chairman

tenb-202410300001660280false00016602802024-10-302024-10-30

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): October 30, 2024

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On October 30, 2024, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended September 30, 2024. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 8.01    Other Events. On October 25, 2024, the Company's Board of Directors approved an increase to the Company's existing share repurchase program of up to an additional $200 million, which is also announced in the press release furnished as Exhibit 99.1 to this report. Repurchases under the share repurchase program may be made in the open market, in privately negotiated transactions, or in such other manner as determined by the Company, including through repurchase plans complying with the rules and regulations of the Securities and Exchange Commission. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Third Quarter 2024 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on October 30, 2024, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:October 30, 2024By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202407310001660280false00016602802024-07-312024-07-31

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): July 31, 2024

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On July 31, 2024, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended June 30, 2024. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Second Quarter 2024 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on July 31, 2024, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:July 31, 2024By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202405010001660280false00016602802024-05-012024-05-01

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): May 1, 2024

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On May 1, 2024, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended March 31, 2024. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces First Quarter 2024 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on May 1, 2024, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:May 1, 2024By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202402060001660280false00016602802024-02-062024-02-06

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): February 6, 2024

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland, 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On February 6, 2024, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter and full year ended December 31, 2023. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Fourth Quarter and Full Year 2023 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on February 6, 2024, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:February 6, 2024By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202311010001660280false00016602802023-11-012023-11-01

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): November 1, 2023

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On November 1, 2023, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended September 30, 2023. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Third Quarter 2023 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on November 1, 2023, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:November 1, 2023By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202307250001660280false00016602802023-07-252023-07-25

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): July 25, 2023

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On July 25, 2023, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended June 30, 2023. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Second Quarter 2023 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on July 25, 2023, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:July 25, 2023By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202304240001660280false00016602802023-04-242023-04-24

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): April 24, 2023

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On April 24, 2023, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended March 31, 2023. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces First Quarter 2023 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on April 24, 2023, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:April 24, 2023By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202302070001660280false00016602802023-02-072023-02-07

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): February 7, 2023

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland, 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On February 7, 2023, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter and full year ended December 31, 2022. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Fourth Quarter and Full Year 2022 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on February 7, 2023, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:February 7, 2023By:/s/ Michelle VonderHaar Michelle VonderHaar Chief Legal Officer and Corporate Secretary

tenb-202210250001660280false00016602802022-10-252022-10-25

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): October 25, 2022

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On October 25, 2022, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended September 30, 2022. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Third Quarter 2022 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on October 25, 2022, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:October 25, 2022By:/s/ David Bartholomew David Bartholomew Interim General Counsel and Assistant Corporate Secretary

tenb-202207260001660280false00016602802022-07-262022-07-26

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): July 26, 2022

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On July 26, 2022, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended June 30, 2022. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Second Quarter 2022 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on July 26, 2022, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:July 26, 2022By:/s/ Stephen A. Riddick Stephen A. Riddick General Counsel and Corporate Secretary

tenb-202204260001660280false00016602802022-04-262022-04-26

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): April 26, 2022

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On April 26, 2022, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended March 31, 2022. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces First Quarter 2022 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on April 26, 2022, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:April 26, 2022By:/s/ Stephen A. Riddick Stephen A. Riddick General Counsel and Corporate Secretary

tenb-202202010001660280false00016602802022-02-012022-02-01

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): February 1, 2022

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland, 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On February 1, 2022, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter and full year ended December 31, 2021. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Fourth Quarter and Full Year 2021 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on February 1, 2022, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:February 1, 2022By:/s/ Stephen A. Riddick Stephen A. Riddick General Counsel and Corporate Secretary

tenb-202110260001660280false00016602802021-10-262021-10-26

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORM 8-K

CURRENT REPORT

Pursuant to Section 13 or 15(d) of The Securities Exchange Act of 1934

Date of report (Date of earliest event reported): October 26, 2021

TENABLE HOLDINGS, INC.

(Exact name of registrant as specified in its charter)

Delaware001-3860047-5580846 (State or other jurisdiction of incorporation or organization)(Commission File Number)(I.R.S. Employer Identification Number)

6100 Merriweather Drive, Columbia, Maryland 21044 (Address of principal executive offices, including zip code)

(410) 872-0555 (Registrant’s telephone number, including area code)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions:

☐Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) ☐Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) ☐Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) ☐Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Securities registered pursuant to Section 12(b) of the Act:

Title of each classTrading Symbol(s)Name of each exchange on which registered Common Stock, par value $0.01 per shareTENBThe Nasdaq Stock Market LLC

Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).

Emerging growth company ☐

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐

Item 2.02    Results of Operations and Financial Condition. On October 26, 2021, Tenable Holdings, Inc. (the "Company") reported financial results for the quarter ended September 30, 2021. A copy of the press release is furnished as Exhibit 99.1 to this report and incorporated by reference. The information in this Item 2.02 of this Current Report on 8-K (including Exhibit 99.1) is furnished and shall not be deemed “filed” for purposes of Section 18 of the Securities Exchange Act of 1934, as amended, or subject to the liabilities of that section or Sections 11 and 12(a)(2) of the Securities Act of 1933, as amended. The information shall not be deemed incorporated by reference into any other filing with the Securities and Exchange Commission made by the Company, whether made before or after today’s date, regardless of any general incorporation language in such filing, except as shall be expressly set forth by specific references in such filing. Item 9.01    Financial Statements and Exhibits. (d)     Exhibits

Exhibit NumberDescription 99.1Press release — "Tenable Announces Third Quarter 2021 Financial Results"

101.SCHInline XBRL Taxonomy Extension Schema Document. 101.LABInline XBRL Taxonomy Extension Label Linkbase Document. 101.PREInline XBRL Taxonomy Extension Presentation Linkbase Document. 104The cover page from Tenable's 8-K filed on October 26, 2021, formatted in Inline XBRL.

SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized.

TENABLE HOLDINGS, INC.

Date:October 26, 2021By:/s/ Stephen A. Riddick Stephen A. Riddick General Counsel and Corporate Secretary