LIE SEAN (Chief Technology Officer) sold 3.4% of their position (21.26K shares) of CEREBRAS SYSTEMS INC. on the open market

Open‑market sale worth $4.72M — a minor trim. Review remaining holdings and any 10b5‑1 plan disclosures.

S · 26 sales

LIE SEAN

Filed: 8/21/2026ACC: 0001628280-26-058312

InsiderLIE SEANCIK 2132472

→

IssuerCEREBRAS SYSTEMS INC.CIK 2021728

Officer10% Owner· Chief Technology Officer

Since May 2026

-21.26K

Net shares

Net seller

$4.72M

Total sold

Open market trades

0B · 26S

Total transactions

616.71K acquired · 637.96K disposed

Non-Derivative Transactions27

Class A Common Stock

Direct

C · Conversion

+616.71K

Price / share

—

Trade value

—

% of position

New position

8/18/2026

0.00→616.71K

Class A Common Stock

Direct

S · Sale

−1.00

Price / share

$214.85

Trade value

$214.85

% of position

0.0%

8/18/2026

616.71K→616.71K

Class A Common Stock

Direct

S · Sale

−1.06K

Price / share

$215.67

Trade value

$228.39K

% of position

0.2%

8/18/2026

616.71K→615.65K

Class A Common Stock

Direct

S · Sale

−1.81K

Price / share

$216.40

Trade value

$391.03K

% of position

0.3%

8/18/2026

615.65K→613.84K

Class A Common Stock

Direct

S · Sale

−1.34K

Price / share

$217.58

Trade value

$292.43K

% of position

0.2%

8/18/2026

613.84K→612.50K

Class A Common Stock

Direct

S · Sale

−1.67K

Price / share

$218.54

Trade value

$364.96K

% of position

0.3%

8/18/2026

612.50K→610.83K

Class A Common Stock

Direct

S · Sale

−1.89K

Price / share

$219.58

Trade value

$415.88K

% of position

0.3%

8/18/2026

610.83K→608.93K

Class A Common Stock

Direct

S · Sale

−3.72K

Price / share

$220.43

Trade value

$820.66K

% of position

0.6%

8/18/2026

608.93K→605.21K

Class A Common Stock

Direct

S · Sale

−3.41K

Price / share

$221.47

Trade value

$754.99K

% of position

0.6%

8/18/2026

605.21K→601.80K

Class A Common Stock

Direct

S · Sale

−1.60K

Price / share

$222.42

Trade value

$355.65K

% of position

0.3%

8/18/2026

601.80K→600.20K

Class A Common Stock

Direct

S · Sale

−492.00

Price / share

$223.54

Trade value

$109.98K

% of position

0.1%

8/18/2026

600.20K→599.71K

Class A Common Stock

Direct

S · Sale

−202.00

Price / share

$224.52

Trade value

$45.35K

% of position

0.0%

8/18/2026

599.71K→599.51K

Class A Common Stock

Direct

S · Sale

−335.00

Price / share

$225.51

Trade value

$75.55K

% of position

0.1%

8/18/2026

599.51K→599.17K

Class A Common Stock

Direct

S · Sale

−457.00

Price / share

$226.46

Trade value

$103.49K

% of position

0.1%

8/18/2026

599.17K→598.71K

Class A Common Stock

Direct

S · Sale

−347.00

Price / share

$227.37

Trade value

$78.90K

% of position

0.1%

8/18/2026

598.71K→598.37K

Class A Common Stock

Direct

S · Sale

−95.00

Price / share

$228.53

Trade value

$21.71K

% of position

0.0%

8/18/2026

598.37K→598.27K

Class A Common Stock

Direct

S · Sale

−147.00

Price / share

$229.46

Trade value

$33.73K

% of position

0.0%

8/18/2026

598.27K→598.13K

Class A Common Stock

Direct

S · Sale

−47.00

Price / share

$230.67

Trade value

$10.84K

% of position

0.0%

8/18/2026

598.13K→598.08K

Class A Common Stock

Direct

S · Sale

−243.00

Price / share

$231.57

Trade value

$56.27K

% of position

0.0%

8/18/2026

598.08K→597.84K

Class A Common Stock

Direct

S · Sale

−277.00

Price / share

$232.62

Trade value

$64.44K

% of position

0.0%

8/18/2026

597.84K→597.56K

Class A Common Stock

Direct

S · Sale

−224.00

Price / share

$233.31

Trade value

$52.26K

% of position

0.0%

8/18/2026

597.56K→597.33K

Class A Common Stock

Direct

S · Sale

−590.00

Price / share

$234.47

Trade value

$138.34K

% of position

0.1%

8/18/2026

597.33K→596.74K

Class A Common Stock

Direct

S · Sale

−301.00

Price / share

$235.50

Trade value

$70.89K

% of position

0.1%

8/18/2026

596.74K→596.44K

Class A Common Stock

Direct

S · Sale

−203.00

Price / share

$236.43

Trade value

$48K

% of position

0.0%

8/18/2026

596.44K→596.24K

Class A Common Stock

Direct

S · Sale

−11.00

Price / share

$237.23

Trade value

$2.61K

% of position

0.0%

8/18/2026

596.24K→596.23K

Class A Common Stock

Direct

S · Sale

−9.00

Price / share

$238.78

Trade value

$2.15K

% of position

0.0%

8/18/2026

596.23K→596.22K

Class A Common Stock

Direct

S · Sale

−771.00

Price / share

$240.01

Trade value

$185.05K

% of position

0.1%

8/18/2026

596.22K→595.45K

Total

Net shares

+595.45K

Net value

-$4.72M

Security	Date	Type	Shares	Price / Share	Trade Value	% of Position	Held Before	Held After
Class A Common Stock Direct	8/18/2026	C · Conversion	+616.71K	—	—	New position	0.00	616.71K
Class A Common Stock Direct	8/18/2026	S · Sale	−1.00	$214.85	$214.85	0.0%	616.71K	616.71K
Class A Common Stock Direct	8/18/2026	S · Sale	−1.06K	$215.67	$228.39K	0.2%	616.71K	615.65K
Class A Common Stock Direct	8/18/2026	S · Sale	−1.81K	$216.40	$391.03K	0.3%	615.65K	613.84K
Class A Common Stock Direct	8/18/2026	S · Sale	−1.34K	$217.58	$292.43K	0.2%	613.84K	612.50K
Class A Common Stock Direct	8/18/2026	S · Sale	−1.67K	$218.54	$364.96K	0.3%	612.50K	610.83K
Class A Common Stock Direct	8/18/2026	S · Sale	−1.89K	$219.58	$415.88K	0.3%	610.83K	608.93K
Class A Common Stock Direct	8/18/2026	S · Sale	−3.72K	$220.43	$820.66K	0.6%	608.93K	605.21K
Class A Common Stock Direct	8/18/2026	S · Sale	−3.41K	$221.47	$754.99K	0.6%	605.21K	601.80K
Class A Common Stock Direct	8/18/2026	S · Sale	−1.60K	$222.42	$355.65K	0.3%	601.80K	600.20K
Class A Common Stock Direct	8/18/2026	S · Sale	−492.00	$223.54	$109.98K	0.1%	600.20K	599.71K
Class A Common Stock Direct	8/18/2026	S · Sale	−202.00	$224.52	$45.35K	0.0%	599.71K	599.51K
Class A Common Stock Direct	8/18/2026	S · Sale	−335.00	$225.51	$75.55K	0.1%	599.51K	599.17K
Class A Common Stock Direct	8/18/2026	S · Sale	−457.00	$226.46	$103.49K	0.1%	599.17K	598.71K
Class A Common Stock Direct	8/18/2026	S · Sale	−347.00	$227.37	$78.90K	0.1%	598.71K	598.37K
Class A Common Stock Direct	8/18/2026	S · Sale	−95.00	$228.53	$21.71K	0.0%	598.37K	598.27K
Class A Common Stock Direct	8/18/2026	S · Sale	−147.00	$229.46	$33.73K	0.0%	598.27K	598.13K
Class A Common Stock Direct	8/18/2026	S · Sale	−47.00	$230.67	$10.84K	0.0%	598.13K	598.08K
Class A Common Stock Direct	8/18/2026	S · Sale	−243.00	$231.57	$56.27K	0.0%	598.08K	597.84K
Class A Common Stock Direct	8/18/2026	S · Sale	−277.00	$232.62	$64.44K	0.0%	597.84K	597.56K
Class A Common Stock Direct	8/18/2026	S · Sale	−224.00	$233.31	$52.26K	0.0%	597.56K	597.33K
Class A Common Stock Direct	8/18/2026	S · Sale	−590.00	$234.47	$138.34K	0.1%	597.33K	596.74K
Class A Common Stock Direct	8/18/2026	S · Sale	−301.00	$235.50	$70.89K	0.1%	596.74K	596.44K
Class A Common Stock Direct	8/18/2026	S · Sale	−203.00	$236.43	$48K	0.0%	596.44K	596.24K
Class A Common Stock Direct	8/18/2026	S · Sale	−11.00	$237.23	$2.61K	0.0%	596.24K	596.23K
Class A Common Stock Direct	8/18/2026	S · Sale	−9.00	$238.78	$2.15K	0.0%	596.23K	596.22K
Class A Common Stock Direct	8/18/2026	S · Sale	−771.00	$240.01	$185.05K	0.1%	596.22K	595.45K
Total			+595.45K		-$4.72M

Derivative Transactions1

Class B Common Stock

Direct

C · Conversion

Converts to

Class A Common Stock

616.71K shares

−616.71K

Strike price

Held after

7.58M

Exercisable

—

8/18/2026

Security	Converts To	Date	Type	Shares	Strike Price	Exercisable	Held After
Class B Common Stock Direct	Class A Common Stock616.71K shares	8/18/2026	C · Conversion	−616.71K		—	7.58M

Non-Derivative Holdings (Post-Transaction)0

No non-derivative holdings reported

Derivative Holdings (Post-Transaction)1

Class B Common Stock

Indirect

Underlying security

Class A Common Stock

Underlying shares

180.60K

Shares owned

180.60K

Exercise price

Expiration

—

Exercise window

—

Total

Underlying

180.60K

Owned

180.60K

Security	Underlying	Exercise Price	Exercise Window	Expiration	Underlying Shares	Shares Owned
Class B Common Stock Indirect	Class A Common Stock		—	—	180.60K	180.60K
Total					180.60K	180.60K