Company · Ownership research

SELLAS Life Sciences Group, Inc. SLS

CIK 0001390478 · CUSIP 81642T209

Insider trading Initial holdings Institutional holders

Quarter-end disclosures, not live holdings.

Several CUSIPs are reported for this company; this page shows CUSIP 81642T209 (SLS), not CUSIP 81642T959 (SLS), CUSIP 81642T909 (SLS), and does not merge CUSIPs.

This page lists the top 20 of 80 rows by value; the complete set is available through the API.

Some filings reported values in thousands; those figures were scaled ×1,000 to dollars.

Top 20 institutions

Weight means this stock's share of the manager's own portfolio.

By reported value

#	Manager	Value	Manager weight	Change vs prior	Source
01	VANGUARD GROUP INC CIK 102909 · View history	$14.57M 6,654,799 shares	0.00%	+3.82M(+134.40%)Added	SEC filing ↗ Aug 11, 2025	▾
02	BlackRock, Inc. CIK 2012383 · View history	$10.05M 4,590,273 shares	0.00%	+4.05M(+752.50%)Added	SEC filing ↗ Aug 12, 2025	▾
03	MARSHALL WACE, LLP CIK 1318757 · View history	$5.95M 2,715,489 shares	0.01%	+2.70M(+23,550.00%)Added	SEC filing ↗ Aug 13, 2025	▾
04	GEODE CAPITAL MANAGEMENT, LLC CIK 1214717 · View history	$4.82M 2,200,428 shares	0.00%	+1.38M(+168.20%)Added	SEC filing ↗ Aug 8, 2025	▾
05	SUSQUEHANNA INTERNATIONAL GROUP, LLP CIK 1446194 · View history	$3.26M 1,489,672 shares	0.00%	+800.98K(+116.30%)Added	SEC filing ↗ Aug 14, 2025	▾
06	MILLENNIUM MANAGEMENT LLC CIK 1273087 · View history	$2.47M 1,127,225 shares	0.00%	+1.13MNew	SEC filing ↗ Aug 14, 2025	▾
07	STATE STREET CORP CIK 93751 · View history	$2.44M 1,112,705 shares	0.00%	+835.68K(+301.70%)Added	SEC filing ↗ Aug 14, 2025	▾
08	MORGAN STANLEY CIK 895421 · View history	$2.38M 1,084,478 shares	0.00%	+1.02M(+1,532.00%)Added	SEC filing ↗ Aug 14, 2025	▾
09	Nuveen, LLC CIK 1871926 · View history	$2.13M 971,329 shares	0.00%	+971.33KNew	SEC filing ↗ Aug 12, 2025	▾
10	NORTHERN TRUST CORP CIK 73124 · View history	$1.53M 698,493 shares	0.00%	+534.10K(+324.90%)Added	SEC filing ↗ Aug 13, 2025	▾
11	GOLDMAN SACHS GROUP INC CIK 886982 · View history	$1.02M 465,506 shares	0.00%	+465.51KNew	SEC filing ↗ Aug 14, 2025	▾
12	GSA CAPITAL PARTNERS LLP CIK 1362033 · View history	$934.00K 426,584 shares	0.07%	+403.86K(+1,777.00%)Added	SEC filing ↗ Jul 22, 2025	▾
13	UBS Group AG CIK 1610520 · View history	$678.21K 309,687 shares	0.00%	+247.46K(+397.60%)Added	SEC filing ↗ Aug 14, 2025	▾
14	CHARLES SCHWAB INVESTMENT MANAGEMENT INC CIK 884546 · View history	$644.09K 294,106 shares	0.00%	+277.87K(+1,711.20%)Added	SEC filing ↗ Aug 12, 2025	▾
15	Anson Funds Management LP CIK 1491072 · View history	$602.25K 275,000 shares	0.11%	-7.30M(-96.40%)Reduced	SEC filing ↗ Aug 14, 2025	▾
16	Opus Capital Group, LLC CIK 1330325 · View history	$526.00K 240,000 shares	0.06%	+500(+0.20%)Added	SEC filing ↗ Jul 31, 2025	▾
17	Bank of New York Mellon Corp CIK 1390777 · View history	$441.20K 201,460 shares	0.00%	+201.46KNew	SEC filing ↗ Aug 5, 2025	▾
18	TWO SIGMA INVESTMENTS, LP CIK 1179392 · View history	$432.84K 197,642 shares	0.00%	+149.35K(+309.30%)Added	SEC filing ↗ Aug 14, 2025	▾
19	BARCLAYS PLC CIK 312069 · Amended · View history	$378.44K 172,803 shares	0.00%	+172.80KNew	SEC filing ↗ Feb 27, 2026	▾
20	RHUMBLINE ADVISERS CIK 1115418 · View history	$297.37K 135,789 shares	0.00%	+135.79KNew	SEC filing ↗ Aug 12, 2025	▾

Showing 20 / 80 institutions. The complete set is available through the API.

Coverage & totals by quarter

Reporting institutions

Cancelled or null records excluded

Disclosed shares

26,795,029

Not deduplicated across managers

Disclosed value

$58.68M

Not market cap or free float

Reporting institutions by quarter

Counts also change with data coverage and reporting entities; they do not measure net buying. Distinct managers with a live stock row in this CUSIP; totals may include overlapping filings and are not a share of the company.

SELLAS Life Sciences Group, Inc. · Q2 2025

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Sources, coverage & how to read this data

Figures are as reported to the SEC and merged with later amendments where Akkru could match them. Preview limits apply to what is listed, not to the totals, which come from the complete reported data. Nothing is zero-filled: a missing quarter or month is shown as missing.