Comparable stake leader
Vassilios Gregoriou
SEC ownership of ADVENT TECHNOLOGIES HOLDINGS, INC.
Top holders, 13D/G large-stake signals, insider positions, and transaction flow tied to CIK 0001744494.
Disclosed value leader
Vassilios Gregoriou
Comparable rows
0/14
Latest evidence
15 Feb 2024
- Public ticker
- ADNH on OTC
- Parsed ownership sources
-
3/4/5
Source: Parsed SEC ownership filingsUse: Compare filing families carefully
- Largest SEC-reported holder
-
Vassilios Gregoriou
Ranking: Comparable ownership first, then disclosed value
- Latest parsed ownership date
-
15 Feb 2024
Freshness: Most recent filing date in this holder set
- Issuer CIK
- 0001744494
- Issuer location
- Boston, MA
Ownership snapshot
CIK-linked ownership evidence from parsed SEC filings.
1 signal
Issuer
Names, identifiers, and filing context for this profile.
2 identity fields
Ownership snapshot
Top shareholders of ADVENT TECHNOLOGIES HOLDINGS, INC. (13F + 13D/G + 3/4/5)
Grouped by holder across the latest SEC ownership disclosures. Start with comparable ownership when available, then verify the linked 13F, 13D/G, or 3/4/5 evidence.
Comparable stake leader
Vassilios Gregoriou
Disclosed value leader
Vassilios Gregoriou
Comparable rows
0/14
Latest evidence
15 Feb 2024
3/4/5
Highest disclosed value: $3,381,232
14 rows are not safely comparable across share classes.
Showing 1-8 of 14 holder rows.
Quick read
Vassilios Gregoriou has the largest disclosed position value at $3.38M.
0 of 14 rows have a safely comparable ownership percentage. Use this as a filing-backed starting point, then open the detailed table for source links, reporting role, position value, share count, and filing date.
Open SEC evidence
Opens Vassilios Gregoriou's linked filing trail.
Disclosed position value
Top 5
Vassilios Gregoriou
$3.38M
Christos Kaskavelis
$2.15M
Emory Sayre de Castro
$1.28M
James F. Coffey
$465.9K
John Hunter William
$236.7K
Value bars compare disclosed positions; verify each figure against the linked filing evidence.
Detailed SEC evidence table Showing 1-8 of 14 holder rows
| Holder | Evidence | Ownership % | Position | 12M Net Δ | As of |
|---|---|---|---|---|---|
| Vassilios Gregoriou |
3/4/5
CEO, Chair, Director, 10%+ Owner
|
—
class O/S missing
|
$3,381,232
6,367,669 shares
|
— | 06 Sep 2023 |
| Christos Kaskavelis |
3/4/5
CMO
|
—
class O/S missing
|
$2,150,501
4,049,907 shares
|
— | 11 Jun 2021 |
| Emory Sayre de Castro |
3/4/5
CTO, Director
|
—
class O/S missing
|
$1,281,570
2,413,503 shares
|
— | 06 Feb 2023 |
| James F. Coffey |
3/4/5
COO, GC
|
—
class O/S missing
|
$465,897
877,396 shares
|
— | 06 Feb 2023 |
| John Hunter William |
3/4/5
President and CFO, Director
|
—
mixed-class rows
|
$236,717
791,588 shares
mixed-class rows
|
— | 11 Jun 2021 |
| Panoraia Gourdoupi |
3/4/5
Director
|
—
class O/S missing
|
$201,507
379,485 shares
|
— | 12 Jan 2023 |
| Naiem Hussain |
3/4/5
Chief Financial Officer
|
—
mixed-class rows
|
$133,695
418,558 shares
mixed-class rows
|
— | 15 Feb 2024 |
| Kevin L. Brackman |
3/4/5
CFO
|
—
class O/S missing
|
$93,709
176,477 shares
|
— | 06 Sep 2023 |
How to read this table
Rows are grouped by holder and ranked first by SEC-reported ownership % when it is safely comparable, then by disclosed holdings value. — indicates unavailable or non-comparable values; "mixed-class rows" means the latest filing spans non-comparable classes.
Forms 3/4/5 flow
Insider trading overview
Insider buy and sell flow is broadly balanced over the last 12 months. No Buy or Sell transactions have been reported since 18 Aug 2025.
Buys
$0
Insiders: 0
Sells
$0
Insiders: 0
Net
$0
Shares: 0
Window
Last 12 months
4 rolling buckets
Buy value
Sell value
Shares: 0
Shares: 0
| Window (months) | Buy shares | Sell shares | Buy value | Sell value | Net value |
|---|---|---|---|---|---|
| 0-3 | 0 | 0 | $0 | $0 | $0 |
| 3-6 | 0 | 0 | $0 | $0 | $0 |
| 6-9 | 0 | 0 | $0 | $0 | $0 |
| 9-12 | 0 | 0 | $0 | $0 | $0 |
Reporting owners
Insider holders from Forms 3/4/5
Showing 1-20 of 21 reporting-owner rows connected to ADVENT TECHNOLOGIES HOLDINGS, INC.. Open a relationship link for the CIK-to-CIK filing trail.
Rows
21
Largest Forms 3/4/5 holder
Vassilios Gregoriou
Net 12M change
$0
Latest report
31 Dec 2024
| Name | Relationship | Holdings Value | Past Year Net Change | Change % | Valuation | Report Date |
|---|---|---|---|---|---|---|
| Vassilios Gregoriou | CEO, Chair, Director, 10%+ Owner | $3,381,232 | Filing P/S | 06 Sep 2023 | ||
| Christos Kaskavelis | Cmo | $2,150,501 | Mixed | 11 Jun 2021 | ||
| Emory Sayre de Castro | CTO, Director | $1,281,570 | Mixed | 06 Feb 2023 | ||
| James F. Coffey | Coo, Gc | $465,897 | Mixed | 06 Feb 2023 | ||
| John Hunter William | President and CFO, Director | $236,717 | Mixed | 11 Jun 2021 | ||
| Panoraia Gourdoupi | Director | $201,507 | Mixed | 12 Jan 2023 | ||
| Naiem Hussain | Chief Financial Officer | $133,695 | Mixed | 15 Feb 2024 | ||
| Kevin L. Brackman | Cfo | $93,709 | Filing P/S | 06 Sep 2023 | ||
| Anggelos Skutaris | Director | $44,508 | Mixed | 15 Jun 2022 | ||
| Lawrence Epstein | Director | $35,904 | Mixed | 15 Jun 2022 | ||
| Wayne Threatt | Director | $34,258 | Mixed | 15 Jun 2022 | ||
| Lawrence M. Clark Jr. | Director | $28,835 | Mixed | 11 Jun 2021 | ||
| Katherine E. Fleming | Director | $10,250 | Mixed | 11 Jun 2021 | ||
| Katrina Fritz | Director | $10,250 | Mixed | 11 Jun 2021 | ||
| Seth M. Lukash | Director | Mixed | 04 Nov 2024 | |||
| Avtar Dhaliwal | Director | Mixed | 31 Dec 2024 | |||
| Joseph Patrick Celia | Director | Mixed | 04 Nov 2024 | |||
| Mcconnell von | Director | Mixed | 04 Nov 2022 | |||
| Marc Seelenfreund | Director | Mixed | 30 Aug 2024 | |||
| Robert William Schwartz | Director | Mixed | 31 Dec 2024 |
Recent insider transactions for ADVENT TECHNOLOGIES HOLDINGS, INC.
Showing up to 300 recent insider transactions from the last 12 months.
| Insider | Symbol | Class | Transaction | % | SEC-reported value | SEC-reported price | Shares | Shares owned | Date | Ownership |
|---|---|---|---|---|---|---|---|---|---|---|
| No insider transactions were found in the last 12 months for this issuer. | ||||||||||
* marks a reported price that did not pass the local price check.