THURMOND MARK C. (Co-Chief Executive Officer) exercised options at TENABLE HOLDINGS, INC.

Option exercise — a mechanical event triggered by vesting or expiry. Not a discretionary conviction trade.

M · 7 exercises

THURMOND MARK C.

Filed: 2/25/2026ACC: 0001651579-26-000002

InsiderTHURMOND MARK C.CIK 1651579

→

IssuerTENABLE HOLDINGS, INC.CIK 1660280

DirectorOfficer· Co-Chief Executive Officer

Since Feb 2026

-21.28K

Net shares

Net seller

$373.5K

Total sold

Open market trades

0B · 0S

Total transactions

63.32K acquired · 84.60K disposed

Non-Derivative Transactions14

Common Stock

Direct

M · Option Exercise

+1.36K

Price / share

—

Trade value

—

% of position

1.2%

2/23/2026

113.64K→115K

Common Stock

Direct

F · Tax Withholding

−401.00

Price / share

$17.55

Trade value

$7.04K

% of position

0.3%

2/23/2026

115K→114.60K

Common Stock

Direct

M · Option Exercise

+1.16K

Price / share

—

Trade value

—

% of position

1.0%

2/23/2026

114.60K→115.77K

Common Stock

Direct

F · Tax Withholding

−342.00

Price / share

$17.55

Trade value

$6K

% of position

0.3%

2/23/2026

115.77K→115.42K

Common Stock

Direct

M · Option Exercise

+2.27K

Price / share

—

Trade value

—

% of position

2.0%

2/23/2026

115.42K→117.69K

Common Stock

Direct

F · Tax Withholding

−666.00

Price / share

$17.55

Trade value

$11.69K

% of position

0.6%

2/23/2026

117.69K→117.02K

Common Stock

Direct

M · Option Exercise

+3.86K

Price / share

—

Trade value

—

% of position

3.3%

2/23/2026

117.02K→120.88K

Common Stock

Direct

F · Tax Withholding

−1.86K

Price / share

$17.55

Trade value

$32.73K

% of position

1.5%

2/23/2026

120.88K→119.02K

Common Stock

Direct

M · Option Exercise

+3.71K

Price / share

—

Trade value

—

% of position

3.1%

2/23/2026

119.02K→122.73K

Common Stock

Direct

F · Tax Withholding

−1.09K

Price / share

$17.55

Trade value

$19.13K

% of position

0.9%

2/23/2026

122.73K→121.64K

Common Stock

Direct

M · Option Exercise

+46.59K

Price / share

—

Trade value

—

% of position

38.3%

2/23/2026

121.64K→168.22K

Common Stock

Direct

F · Tax Withholding

−15.63K

Price / share

$17.55

Trade value

$274.39K

% of position

9.3%

2/23/2026

168.22K→152.59K

Common Stock

Direct

M · Option Exercise

+4.37K

Price / share

—

Trade value

—

% of position

2.9%

2/23/2026

152.59K→156.96K

Common Stock

Direct

F · Tax Withholding

−1.28K

Price / share

$17.55

Trade value

$22.52K

% of position

0.8%

2/23/2026

156.96K→155.68K

Total

Net shares

+42.04K

Net value

-$373.50K

Security	Date	Type	Shares	Price / Share	Trade Value	% of Position	Held Before	Held After
Common Stock Direct	2/23/2026	M · Option Exercise	+1.36K	—	—	1.2%	113.64K	115K
Common Stock Direct	2/23/2026	F · Tax Withholding	−401.00	$17.55	$7.04K	0.3%	115K	114.60K
Common Stock Direct	2/23/2026	M · Option Exercise	+1.16K	—	—	1.0%	114.60K	115.77K
Common Stock Direct	2/23/2026	F · Tax Withholding	−342.00	$17.55	$6K	0.3%	115.77K	115.42K
Common Stock Direct	2/23/2026	M · Option Exercise	+2.27K	—	—	2.0%	115.42K	117.69K
Common Stock Direct	2/23/2026	F · Tax Withholding	−666.00	$17.55	$11.69K	0.6%	117.69K	117.02K
Common Stock Direct	2/23/2026	M · Option Exercise	+3.86K	—	—	3.3%	117.02K	120.88K
Common Stock Direct	2/23/2026	F · Tax Withholding	−1.86K	$17.55	$32.73K	1.5%	120.88K	119.02K
Common Stock Direct	2/23/2026	M · Option Exercise	+3.71K	—	—	3.1%	119.02K	122.73K
Common Stock Direct	2/23/2026	F · Tax Withholding	−1.09K	$17.55	$19.13K	0.9%	122.73K	121.64K
Common Stock Direct	2/23/2026	M · Option Exercise	+46.59K	—	—	38.3%	121.64K	168.22K
Common Stock Direct	2/23/2026	F · Tax Withholding	−15.63K	$17.55	$274.39K	9.3%	168.22K	152.59K
Common Stock Direct	2/23/2026	M · Option Exercise	+4.37K	—	—	2.9%	152.59K	156.96K
Common Stock Direct	2/23/2026	F · Tax Withholding	−1.28K	$17.55	$22.52K	0.8%	156.96K	155.68K
Total			+42.04K		-$373.50K

Derivative Transactions7

Performance Restricted Stock Units

Direct

M · Option Exercise

Converts to

Common Stock

1.36K shares

−1.36K

Strike price

Held after

0.00

Exercisable

—

2/23/2026

Performance Restricted Stock Units

Direct

M · Option Exercise

Converts to

Common Stock

1.16K shares

−1.16K

Strike price

Held after

4.65K

Exercisable

—

2/23/2026

Performance Restricted Stock Units

Direct

M · Option Exercise

Converts to

Common Stock

2.27K shares

−2.27K

Strike price

Held after

18.14K

Exercisable

—

2/23/2026

Restricted Stock Units

Direct

M · Option Exercise

Converts to

Common Stock

3.86K shares

−3.86K

Strike price

Held after

0.00

Exercisable

—

2/23/2026

Restricted Stock Units

Direct

M · Option Exercise

Converts to

Common Stock

3.71K shares

−3.71K

Strike price

Held after

14.85K

Exercisable

—

2/23/2026

Restricted Stock Units

Direct

M · Option Exercise

Converts to

Common Stock

46.59K shares

−46.59K

Strike price

Held after

93.17K

Exercisable

—

2/23/2026

Restricted Stock Units

Direct

M · Option Exercise

Converts to

Common Stock

4.37K shares

−4.37K

Strike price

Held after

34.94K

Exercisable

—

2/23/2026

Security	Converts To	Date	Type	Shares	Exercisable	Held After
Performance Restricted Stock Units Direct	Common Stock1.36K shares	2/23/2026	M · Option Exercise	−1.36K	—	0.00
Performance Restricted Stock Units Direct	Common Stock1.16K shares	2/23/2026	M · Option Exercise	−1.16K	—	4.65K
Performance Restricted Stock Units Direct	Common Stock2.27K shares	2/23/2026	M · Option Exercise	−2.27K	—	18.14K
Restricted Stock Units Direct	Common Stock3.86K shares	2/23/2026	M · Option Exercise	−3.86K	—	0.00
Restricted Stock Units Direct	Common Stock3.71K shares	2/23/2026	M · Option Exercise	−3.71K	—	14.85K
Restricted Stock Units Direct	Common Stock46.59K shares	2/23/2026	M · Option Exercise	−46.59K	—	93.17K
Restricted Stock Units Direct	Common Stock4.37K shares	2/23/2026	M · Option Exercise	−4.37K	—	34.94K