VANDERHOOK CHRISTOPHER (Chief Operating Officer) sold 2.4% of their position (8.78K shares) of VIANT TECHNOLOGY INC. on the open market

Open‑market sale worth $85.4K — a minor trim. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 1 sale

VANDERHOOK CHRISTOPHER

Filed: 9/17/2025ACC: 0001843104-25-000007

InsiderVANDERHOOK CHRISTOPHERCIK 1843104

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IssuerVIANT TECHNOLOGY INC.CIK 1828791

DirectorOfficer· Chief Operating Officer

Since Feb 2021

-636.63K

Net shares

Net seller

$3.09M

Total sold

Open market trades

0B · 1S

Total transactions

313.93K acquired · 950.56K disposed

Non-Derivative Transactions4

Class A Common Stock

Direct

S · Sale

−8.78K

Price / share

$9.73

Trade value

$85.43K

% of position

2.4%

9/15/2025

365.07K→356.28K

Class A Common Stock

Indirect

M · Option Exercise

+313.93K

Price / share

—

Trade value

—

% of position

New position

9/16/2025

0.00→313.93K

Class B Common Stock

Indirect

D · Disposition

−313.93K

Price / share

—

Trade value

—

% of position

3.3%

9/16/2025

9.48M→9.17M

Class A Common Stock

Indirect

D · Disposition

−313.93K

Price / share

$9.56

Trade value

$3M

% of position

New position

9/17/2025

313.93K→0.00

Total

Net shares

−322.71K

Net value

-$3.09M

Security	Date	Type	Shares	Price / Share	Trade Value	% of Position	Held Before	Held After
Class A Common Stock Direct	9/15/2025	S · Sale	−8.78K	$9.73	$85.43K	2.4%	365.07K	356.28K
Class A Common Stock Indirect	9/16/2025	M · Option Exercise	+313.93K	—	—	New position	0.00	313.93K
Class B Common Stock Indirect	9/16/2025	D · Disposition	−313.93K	—	—	3.3%	9.48M	9.17M
Class A Common Stock Indirect	9/17/2025	D · Disposition	−313.93K	$9.56	$3M	New position	313.93K	0.00
Total			−322.71K		-$3.09M

Derivative Transactions1

Class B Units

Indirect

M · Option Exercise

Converts to

Class A Common Stock

313.93K shares

−313.93K

Strike price

Held after

9.17M

Exercisable

—

9/16/2025

Security	Converts To	Date	Type	Shares	Strike Price	Exercisable	Held After
Class B Units Indirect	Class A Common Stock313.93K shares	9/16/2025	M · Option Exercise	−313.93K		—	9.17M

Non-Derivative Holdings (Post-Transaction)5

Class B Common Stock

Indirect

Shares owned301.89K

Class B Common Stock

Indirect

Shares owned301.89K

Class B Common Stock

Indirect

Shares owned301.89K

Class B Common Stock

Indirect

Shares owned301.89K

Class B Common Stock

Direct

Shares owned6.63M

Total

6.63M direct·1.21M indirect7.83M

Security Title	Shares Owned	Ownership Type
Class B Common Stock	301.89K	Indirect
Class B Common Stock	301.89K	Indirect
Class B Common Stock	301.89K	Indirect
Class B Common Stock	301.89K	Indirect
Class B Common Stock	6.63M	Direct
Total	7.83M	6.63M direct·1.21M indirect

Derivative Holdings (Post-Transaction)5

Class B Units

Indirect

Underlying security

Class A Common Stock

Underlying shares

0.00

Shares owned

301.89K

Exercise price

Expiration

—

Exercise window

—

Class B Units

Direct

Underlying security

Class A Common Stock

Underlying shares

0.00

Shares owned

6.63M

Exercise price

Expiration

—

Exercise window

—

Class B Units

Indirect

Underlying security

Class A Common Stock

Underlying shares

0.00

Shares owned

301.89K

Exercise price

Expiration

—

Exercise window

—

Class B Units

Indirect

Underlying security

Class A Common Stock

Underlying shares

0.00

Shares owned

301.89K

Exercise price

Expiration

—

Exercise window

—

Class B Units

Indirect

Underlying security

Class A Common Stock

Underlying shares

0.00

Shares owned

301.89K

Exercise price

Expiration

—

Exercise window

—

Total

Underlying

0.00

Owned

7.83M

Security	Underlying	Exercise Window	Expiration	Shares Owned
Class B Units Indirect	Class A Common Stock	—	—	301.89K
Class B Units Direct	Class A Common Stock	—	—	6.63M
Class B Units Indirect	Class A Common Stock	—	—	301.89K
Class B Units Indirect	Class A Common Stock	—	—	301.89K
Class B Units Indirect	Class A Common Stock	—	—	301.89K
Total				7.83M