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SEC EDGAR · Forms 3/4/5Updated through Oct 30, 2026•42 filings

AMPX

Amprius Technologies, Inc.

Net sales of $80.2K over the last 3 months

1 seller account for the net balance. There is no cluster of three distinct buyers within 30 days. We found no CEO/CFO purchases over 12 months.

How to read this signal

Only open-market P purchases and S sales count toward the signal. Vesting, options, taxes and gifts remain in the source data but do not trigger alerts. Rule 10b5-1 trades are shown as informational.

JSON example

3-month balance

−$80,240

0 buyers · 1 sellers

12-month purchases

$0.00

0 distinct insiders

12-month sales

$80,198,952

6 distinct insiders

Highlighted alerts

11

13 Rule 10b5-1 trades treated as informational

Buying cluster · 30 days

Fewer than three distinct buyers

CEO/CFO purchases · 12 months

No executive purchases found

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Form 4 raw → Raspberry

The value is in what we do not call a signal.

The SEC XML stores every transaction. Raspberry keeps that evidence, reads the footnotes and separates voluntary open-market activity from vesting, option exercises, gifts, tax withholding, stock purchase and dividend reinvestment plans and pre-programmed 10b5-1 trades.

100
Raw transactions
Everything returned by the filing
24
Voluntary view
P/S trades after deterministic checks
76
Administrative noise
Stored, never alerted
51
10b5-1
Shown as informational
SEC ownership XML facts
Code
S
Shares
23,529
Price
$10.34
Footnotes
6

This transaction was effected pursuant to non-discretionary, sell-to-cover arrangements mandated by the issuer to fund tax withholding obligations in connection with the vesting of restricted stock units. The price reported in Column 4 is an average execution price. These shares were sold in multiple transactions at prices ranging from $10.10 to $10.48, inclusive. The reporting person undertakes to provide to the issuer, any security holder of the issuer, or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares sold at each separate price within the range set forth above. Includes 568,750 restricted stock units, each of which represents a contingent right to receive one share of the issuer's common stock, subject to the applicable vesting schedule and conditions of each restricted stock unit. These transfers were made on the same date as bona fide gifts. These securities were transferred by the reporting person to the Rogers Stepien Family Revocable Trust, for which the reporting person and his spouse are co-trustees. These securities are held by the Rogers Stepien Family Revocable Trust, for which the reporting person and his spouse are co-trustees.

Raspberry interpretation
Informational — no alert

Reason: tax_withholding. The filing footnotes identify tax withholding.

Verify in SEC EDGAR

Recent transactions

Voluntary purchases and sales; administrative noise stays hidden.

24 transactions

Stepien Thomas M

Chief Executive Officer

SaleAlert
Shares
8,000
Price
$10.03
Value
$80,240
Open SEC filing

DIXON DONALD R

Director

SaleAlert
Shares
85,000
Price
$17.17
Value
$1,459,212
Open SEC filing

DIXON DONALD R

Director

SaleAlert
Shares
40,000
Price
$19.13
Value
$765,200
Open SEC filing

Stepien Thomas M

Chief Executive Officer

SaleAlert
Shares
2,000
Price
$20.97
Value
$41,940
Open SEC filing

DIXON DONALD R

Director

SaleAlert
Shares
17,895
Price
$17.90
Value
$320,253
Open SEC filing

Sun Kang

Director

Sale 10b5-1
Shares
249,037
Price
$16.78
Value
$4,179,563
Open SEC filing

Sun Kang

Director

Sale 10b5-1
Shares
1,250,963
Price
$15.73
Value
$19,681,151
Open SEC filing

Sun Kang

Director

Sale 10b5-1
Shares
65,046
Price
$19.06
Value
$1,239,705
Open SEC filing

Sun Kang

Director

Sale 10b5-1
Shares
152,823
Price
$18.69
Value
$2,855,696
Open SEC filing

HSIEH Wen Hsuan

Director

SaleAlert
Shares
130,646
Price
$18.22
Value
$2,380,788
Open SEC filing

HSIEH Wen Hsuan

Director

SaleAlert
Shares
282,500
Price
$18.55
Value
$5,239,245
Open SEC filing

Chu Steven

Director

SaleAlert
Shares
5,565
Price
$18.53
Value
$103,145
Open SEC filing

Chu Steven

Director

SaleAlert
Shares
50,000
Price
$18.21
Value
$910,740
Open SEC filing

Chu Steven

Director

SaleAlert
Shares
100,000
Price
$18.65
Value
$1,864,670
Open SEC filing

Chu Steven

Director

SaleAlert
Shares
166,632
Price
$17.92
Value
$2,985,429
Open SEC filing

Stefan Constantin Ionel

Chief Technology Officer

Sale 10b5-1
Shares
39,690
Price
$12.00
Value
$476,351
Open SEC filing

Stefan Constantin Ionel

Chief Technology Officer

Sale 10b5-1
Shares
1,600
Price
$12.00
Value
$19,200
Open SEC filing

Stefan Constantin Ionel

Chief Technology Officer

Sale 10b5-1
Shares
492,827
Price
$12.04
Value
$5,931,912
Open SEC filing

Stefan Constantin Ionel

Chief Technology Officer

Sale 10b5-1
Shares
73,280
Price
$12.00
Value
$879,411
Open SEC filing

Sun Kang

Director

Sale 10b5-1
Shares
43,185
Price
$11.03
Value
$476,274
Open SEC filing

Sun Kang

Director

Sale 10b5-1
Shares
950,548
Price
$11.07
Value
$10,518,669
Open SEC filing

Sun Kang

Director

Sale 10b5-1
Shares
506,267
Price
$10.10
Value
$5,111,474
Open SEC filing

Stefan Constantin Ionel

Chief Technology Officer

Sale 10b5-1
Shares
198,255
Price
$10.51
Value
$2,083,382
Open SEC filing

Sun Kang

Chief Executive Officer

Sale 10b5-1
Shares
1,000,000
Price
$10.60
Value
$10,595,300
Open SEC filing

“Alert” means a voluntary, unscheduled transaction according to the filing; it is not an investment recommendation. Official source: SEC EDGAR.