How many institutions own SION stock?

A company's 13F filings with the Securities and Exchange Commission (SEC) provides investors with comprehensive information about institutional ownership in a listed company, a sign of strength in terms of how many institutions have confidence in that company. The number of institutional investors who currently own SION shares is 121, representing 93.62% of the company's common stock.

Who are the major shareholders selling Sionna Therapeutics, Inc. stock?

ORBIMED ADVISORS LLC, in the last quarter, reduced its stake in SION by -3.87% restricting it's holding to 3.56 million shares of worth nearly $146.53M. RA CAPITAL MANAGEMENT, L.P. also lessened -5.17% of the SION shares from its portfolio, reducing its holding to 9.91 million shares of worth $407.49M. BNP PARIBAS ARBITRAGE, SNC also shunned SION shares holding by -4.87% last quarter which brought its holding to 2.26 thousand shares worth $93.14M.

Investors who are buying SION stock?

As per its latest 13F filing, AMERICAN CENTURY COMPANIES INC increased its stake in SION by 100% in the last quarter. The institutional holder raised its holding to 6.18 thousand shares having worth more than $254.25K. KENNEDY CAPITAL MANAGEMENT LLC also added 100% more shares of SION to its portfolio, raising its holding to 6.75 thousand shares of worth $277.78K. MIRAE ASSET GLOBAL INVESTMENTS CO., LTD. also increased its SION shares holding by 100% which brought its holding to 2.17 thousand shares worth $89.23K.

SION's major insiders: who are they?

The insider with the most stakes in SION is TPG GP A, LLC , 10 percent owner at the company. Additionally, SION stock is highly held by director Thompson Peter A. and director ORBIMED ADVISORS LLC among others.

Did an insider recently sell SION stock?

Company executives, directors, and other insiders own 6.93% percent of Sionna Therapeutics, Inc.'s stock. Within the last six months, there have been 46 transaction(s) in which SION insiders have sold stock, totaling 852.16K shares. Insiders that have sold shares include THOMPSON PETER A., ORBIMED ADVISORS LLC, and TPG GP A, LLC.

Which insider recently purchased SION stock?

There have been 0 transaction(s) during the past 6-months in which Sionna Therapeutics, Inc. insiders have bought stock, totalling 0 shares

How much of SION does insiders own?

Around 84.87M Sionna Therapeutics, Inc. shares are held by insiders, which represents about 6.93% of SION stock.

Who is the insider with the largest stake?

SION 10 percent owner, TPG GP A, LLC holds the largest portfolio of the company's shares. SION shares owned by TPG total nearly 6.49 million.

Which institution holds the most shares in SION?

DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) is the largest institutional owner in SION which holds 970.59 thousand shares worth $39.93M or 2.18% of the total SION shares outstanding followed by PERCEPTIVE ADVISORS LLC with ownership of 1.18 million shares representing 2.65% of the SION ownership. ORBIMED ADVISORS LLC is the third largest stakeholder with 3.56 million shares or 8.01% of the ownership worth more than $146.53M.

Is Sionna Therapeutics, Inc. stock optionable?

Stock options give the owner the ability but not the obligation to buy or sell a security at a predetermined price and date. Stock options can be classified into two types: puts and calls. A put is a bet on falling stock, and a call is a bet on rising stock. As far as the SION is concerned, it is a stock which is not optionable.

Is there a short position on SION's shares?

Number of SION shares short is 3.60M. Shares short is a market sentiment in which investors have sold their shares short in a given stock but have not yet covered them or closed them out.

About how many outstanding SION shares are there?

As of today, 44.14M shares of SION are outstanding.

Is there many float in SION stock?

Float represents the number of tradeable shares in a specific stock. By subtracting restricted and closely-held shares from a firm's total outstanding shares, we can calculate its floating stock. The term "closely-held shares" refers to shares held by employees, major shareholders, and company insiders. At present, SION has 11.04M shares in float.

SION short ratio: what is it?

Short ratio is calculated by dividing the number of short shares, short interest or bets that shareholders will sell short from the average daily volume. A higher ratio indicates longer times needed to repurchase borrowed shares (sold). The short ratio for SION is 22.4.

Sionna Therapeutics (SION) insider trading activity: Get Latest News Today

Stock Outstanding Shares

Making an investment decision in the stock market involves a certain amount of risk, so it's important to thoroughly review a company's stock before making any decisions. Stock float, number of short positions and outstanding shares are among the many factors an investor should take into account.

ShortableYes

OptionableNo

Short Percent Of Outstanding Shares8.16

Short Percent Of Float13.71

Shares Outstanding44.14M

Shares Float11.04M

Shares Short3.60M

Short Ratio22.4

13.71%

Short % of Float

8.16%

Short % of Shares Outstanding

Market Insider

Investors cannot turn a blind eye to insiders as well as institutional ownership. They need to follow insider trades to determine the direction the stock is likely to take.

Major Holders Summary

6.93% Percentage of Shares held by All Insiders

93.62% Percentage of Shares held by All Institutions

100.59% Percentage of Float held by Institutions

121

Number of Institutions Holding Shares

Institutional Ownership

About 93.62% of SION shares are held by financial institutions. DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C) is the top corporate investor, holding 970.59K shares valued at $39.93M. A 2.18% stake in Sionna Therapeutics, Inc. is owned by the company. PERCEPTIVE ADVISORS LLC owns 1.18M shares valued at $48.51M, which translates its holding of 2.65% of the stake in the company.

Date	Holder	% Stake	Shares Held	Total Value ($)	Shares	% Change in Portfolio
Dec 31, 2025	DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C)	2.18%	970.59K	39.93M	0	0
Dec 31, 2025	PERCEPTIVE ADVISORS LLC	2.65%	1.18M	48.51M	0	0
Dec 31, 2025	ORBIMED ADVISORS LLC	8.01%	3.56M	146.53M	-143.3K	-3.87%
Dec 31, 2025	RA CAPITAL MANAGEMENT, L.P.	22.28%	9.91M	407.49M	-540.28K	-5.17%
Dec 31, 2025	AMERICAN CENTURY COMPANIES INC	0.01%	6.18K	254.25K	6.18K	+100.00%
Dec 31, 2025	KENNEDY CAPITAL MANAGEMENT LLC	0.02%	6.75K	277.78K	6.75K	+100.00%
Dec 31, 2025	TPG GP A, LLC	15.17%	6.74M	277.49M	0	0
Dec 31, 2025	MIRAE ASSET GLOBAL INVESTMENTS CO., LTD.	0%	2.17K	89.23K	2.17K	+100.00%
Dec 31, 2025	BNP PARIBAS ARBITRAGE, SNC	0.01%	2.26K	93.14M	-116	-4.87%
Dec 31, 2025	POLICE & FIREMEN'S RETIREMENT SYSTEM OF NEW JERSEY	0.01%	4.23K	174.1K	998	+30.86%
Dec 31, 2025	CIBC PRIVATE WEALTH GROUP, LLC	0.01%	4.5K	185.13K	4.5K	+100.00%
Dec 31, 2025	XTX TOPCO LTD	0.01%	4.93K	202.66K	4.93K	+100.00%
Dec 31, 2025	CITIGROUP INC	0.01%	5.19K	213.31K	4.5K	+654.73%
Dec 31, 2025	LOS ANGELES CAPITAL MANAGEMENT LLC	0.01%	5.19K	197.23K	5.19K	+100.00%
Dec 31, 2025	NEW YORK STATE COMMON RETIREMENT FUND	0.01%	5.3K	218.04K	0	0
Dec 31, 2025	VIRTUS INVESTMENT ADVISERS, INC.	0.01%	6.22K	255.89K	-478	-7.14%
Dec 31, 2025	TWO SIGMA INVESTMENTS, LP	0.01%	6.4K	263.3K	6.4K	+100.00%
Dec 31, 2025	INTECH INVESTMENT MANAGEMENT LLC	0.02%	7.59K	312.21K	103	+1.38%
Dec 31, 2025	METLIFE INVESTMENT MANAGEMENT, LLC	0.02%	8.57K	352.36K	532	+6.62%
Dec 31, 2025	PROFUND ADVISORS LLC	0.02%	9.21K	379.02K	9.21K	+100.00%
Dec 31, 2025	DEUTSCHE BANK AG\	0.02%	10.03K	412.59K	433	+4.51%
Dec 31, 2025	CHINA UNIVERSAL ASSET MANAGEMENT CO., LTD.	0.02%	10.27K	422.59K	5.27K	+105.44%
Dec 31, 2025	SG AMERICAS SECURITIES, LLC	0.02%	10.69K	440K	10.69K	+100.00%
Dec 31, 2025	SQUAREPOINT OPS LLC	0.04%	16.36K	673.05K	6.2K	+60.99%
Dec 31, 2025	WELLS FARGO & COMPANY/MN	0.04%	17.55K	722.05K	9.98K	+131.67%
Dec 31, 2025	RHUMBLINE ADVISERS	0.04%	17.69K	727.92M	454	+2.63%
Dec 31, 2025	NUVEEN, LLC	0.05%	23.73K	976.42K	7.69K	+47.97%
Dec 31, 2025	POLEN CAPITAL MANAGEMENT LLC	0.07%	31.26K	1.29M	0	0
Dec 31, 2025	BANK OF NEW YORK MELLON CORP	0.08%	35.13K	1.45M	7.67K	+27.93%
Dec 31, 2025	SILVERARC CAPITAL MANAGEMENT, LLC	0.09%	41.46K	1.71M	-67.34K	-61.89%
Dec 31, 2025	BANK OF AMERICA CORP /DE/	0.1%	43.57K	1.79M	37.03K	+566.06%
Dec 31, 2025	GAMMA INVESTING LLC	0%	177	7.28K	24	+15.69%
Dec 31, 2025	JENNISON ASSOCIATES LLC	2.51%	1.12M	45.88M	117.9K	+11.82%
Dec 31, 2025	VANGUARD GROUP INC	2.67%	1.18M	48.75M	41.8K	+3.66%
Dec 31, 2025	JPMORGAN CHASE & CO	2.77%	1.23M	50.68M	-746.81K	-37.74%
Dec 31, 2025	BLACKROCK, INC.	2.9%	1.29M	53.14M	446.99K	+52.92%
Dec 31, 2025	BARCLAYS PLC	0.11%	48.17K	1.98M	30.53K	+173.04%
Dec 31, 2025	MORGAN STANLEY	0.11%	49.88K	2.05M	27.04K	+118.40%
Dec 31, 2025	ATLAS VENTURE LIFE SCIENCE ADVISORS, LLC	6.74%	3M	123.24M	-619.93K	-17.15%
Dec 31, 2025	SEVEN GRAND MANAGERS, LLC	0.11%	50K	2.06M	50K	+100.00%
Dec 31, 2025	MANUFACTURERS LIFE INSURANCE COMPANY, THE	0.16%	69.42K	2.87M	37.34K	+116.41%
Dec 31, 2025	ENSIGN PEAK ADVISORS, INC	0.18%	79.86K	3.29M	79.86K	+100.00%
Dec 31, 2025	MILLENNIUM MANAGEMENT LLC	0.18%	80.55K	3.31M	-133.54K	-62.38%
Dec 31, 2025	VIKING GLOBAL INVESTORS LP	7.19%	3.2M	131.45M	0	0
Dec 31, 2025	ENAVATE SCIENCES GP, LLC	5.57%	2.48M	101.95M	0	0
Dec 31, 2025	LONGAEVA PARTNERS L.P.	0.18%	79.73K	3.28M	18.27K	+29.73%
Dec 31, 2025	WELLINGTON MANAGEMENT GROUP LLP	0.09%	38.35K	1.58M	-3.89K	-9.20%
Dec 31, 2025	RAFFERTY ASSET MANAGEMENT, LLC	0.06%	24.69K	1.02M	24.69K	+100.00%
Dec 31, 2025	UBS GROUP AG	0.2%	89.18K	3.67M	42.51K	+91.10%
Dec 31, 2025	TD ASSET MANAGEMENT INC	0.25%	113.35K	4.66M	26.27K	+30.17%
Dec 31, 2025	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	0.28%	123.69K	5.09M	12.19K	+10.93%
Dec 31, 2025	FRANKLIN RESOURCES INC	0.39%	175.48K	7.22M	-66.66K	-27.53%
Dec 31, 2025	SOLEUS CAPITAL MANAGEMENT, L.P.	0.6%	268.5K	11.05M	-145K	-35.07%
Dec 31, 2025	GEODE CAPITAL MANAGEMENT, LLC	0.85%	380.04K	15.64M	63.48K	+20.05%
Dec 31, 2025	EVENTIDE ASSET MANAGEMENT, LLC	1.44%	639.05K	26.29M	639.05K	+100.00%
Dec 31, 2025	STATE STREET CORP	1.56%	693.4K	28.53M	453.2K	+188.68%
Dec 31, 2025	CITADEL ADVISORS LLC	2.45%	1.09M	44.73M	1.05M	+2,926.82%
Dec 31, 2025	DRIEHAUS CAPITAL MANAGEMENT LLC	0.19%	83.85K	3.45M	0	0
Dec 31, 2025	ROCK SPRINGS CAPITAL MANAGEMENT LP	0.22%	99.43K	4.09M	0	0
Dec 31, 2025	AMERIPRISE FINANCIAL INC	0.23%	101.64K	4.18M	-51.51K	-33.63%
Dec 31, 2025	INVESCO LTD.	0.25%	111.16K	4.57M	111.16K	+100.00%
Dec 31, 2025	NORTHERN TRUST CORP	0.25%	112.12K	4.61M	14.41K	+14.74%
Dec 31, 2025	ARTIA GLOBAL PARTNERS LP	0.27%	119.74K	4.93M	119.74K	+100.00%
Dec 31, 2025	ABRDN PLC	1.89%	839.96K	34.56M	-110.59K	-11.63%
Dec 31, 2025	SIREN, L.L.C.	0.67%	300K	12.34M	-25K	-7.69%
Dec 31, 2025	ALPS ADVISORS INC	0.08%	36.65K	1.51M	36.65K	+100.00%
Dec 31, 2025	GOLDMAN SACHS GROUP INC	0.08%	36.27K	1.49M	24.09K	+197.82%
Dec 31, 2025	PROSHARE ADVISORS LLC	0.01%	4.9K	201.71K	4.9K	+100.00%
Dec 31, 2025	ALPHACENTRIC ADVISORS LLC	0.01%	2.72K	111.9K	2.72K	+100.00%
Dec 31, 2025	LEGAL & GENERAL GROUP PLC	0%	1.68K	69.2K	-5.69K	-77.19%
Dec 31, 2025	AMERITAS INVESTMENT PARTNERS, INC.	0%	1.3K	53.56K	43	+3.42%
Dec 31, 2025	GF FUND MANAGEMENT CO. LTD.	0%	876	36.04K	876	+100.00%
Dec 31, 2025	AMALGAMATED BANK	0%	504	21K	83	+19.72%
Dec 31, 2025	ROYAL BANK OF CANADA	0%	489	21K	111	+29.37%
Dec 31, 2025	FARTHER FINANCE ADVISORS, LLC	0%	190	7.82K	190	+100.00%
Dec 31, 2025	ALYESKA INVESTMENT GROUP, L.P.	0.31%	136.22K	5.6M	-50K	-26.85%
Dec 31, 2025	SUPERSTRING CAPITAL MANAGEMENT LP	0.41%	180.59K	7.43M	180.59K	+100.00%
Dec 31, 2025		0.44%	197.07K	8.11B	197.07K	+100.00%
Dec 31, 2025	BAKER BROS. ADVISORS LP	0.9%	400K	16.46M	0	0
Dec 31, 2025	PRICE T ROWE ASSOCIATES INC /MD/	1.87%	831.37K	34.2M	193.61K	+30.36%
Sep 30, 2025	SILVERARC CAPITAL MANAGEMENT, LLC	0.25%	108.8K	3.2M	-77.21K	-41.51%
Sep 30, 2025	JENNISON ASSOCIATES LLC	2.26%	997.38K	29.33M	244.58K	+32.49%
Sep 30, 2025	ABRDN PLC	2.15%	950.55K	27.96M	0	0
Sep 30, 2025	GEODE CAPITAL MANAGEMENT, LLC	0.72%	316.56K	9.31M	27.29K	+9.43%
Sep 30, 2025	BRAIDWELL LP	0.71%	314.01K	9.24M	-767.84K	-70.97%
Sep 30, 2025	AMERIPRISE FINANCIAL INC	0.35%	153.15K	4.5M	-83.66K	-35.33%
Sep 30, 2025	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	0.25%	111.5K	3.28M	18.66K	+20.11%
Sep 30, 2025	VIKING GLOBAL INVESTORS LP	7.24%	3.2M	93.97M	0	0
Sep 30, 2025	ENAVATE SCIENCES GP, LLC	5.62%	2.48M	72.88M	0	0
Sep 30, 2025	PERCEPTIVE ADVISORS LLC	2.67%	1.18M	34.68M	-36.95K	-3.04%
Sep 30, 2025	VANGUARD GROUP INC	2.59%	1.14M	33.62M	512.8K	+81.35%
Sep 30, 2025	DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C)	2.2%	970.59K	28.55M	0	0
Sep 30, 2025	FRANKLIN RESOURCES INC	0.55%	242.15K	7.12M	-257.88K	-51.57%
Sep 30, 2025	STATE STREET CORP	0.54%	240.2K	7.06M	115.68K	+92.90%
Sep 30, 2025	ROCK SPRINGS CAPITAL MANAGEMENT LP	0.23%	99.43K	2.92M	0	0
Sep 30, 2025	NORTHERN TRUST CORP	0.22%	97.71K	2.87M	5.82K	+6.33%
Sep 30, 2025	TD ASSET MANAGEMENT INC	0.2%	87.08K	2.56M	37.12K	+74.28%
Sep 30, 2025	DRIEHAUS CAPITAL MANAGEMENT LLC	0.19%	83.85K	2.47M	0	0
Sep 30, 2025	LONGAEVA PARTNERS L.P.	0.14%	61.46K	1.81M	61.46K	+100.00%
Sep 30, 2025	HOLOCENE ADVISORS, LP	0.11%	50K	1.47M	0	0
Sep 30, 2025	UBS GROUP AG	0.11%	46.67K	1.37M	-4.7K	-9.15%
Sep 30, 2025	WELLINGTON MANAGEMENT GROUP LLP	0.1%	42.23K	1.24M	42.23K	+100.00%
Sep 30, 2025	CITADEL ADVISORS LLC	0.08%	35.92K	1.06M	-93.99K	-72.35%
Sep 30, 2025	MANUFACTURERS LIFE INSURANCE COMPANY, THE	0.07%	32.08K	943.47K	-5.96K	-15.66%
Sep 30, 2025	POLEN CAPITAL MANAGEMENT LLC	0.07%	31.26K	919.3K	14.28K	+84.14%
Sep 30, 2025	MARSHALL WACE, LLP	0.07%	30.1K	885.33K	30.1K	+100.00%
Sep 30, 2025	BARCLAYS PLC	0.04%	17.64K	518.88K	-5.38K	-23.36%
Sep 30, 2025	RHUMBLINE ADVISERS	0.04%	17.24K	507.02K	-430	-2.43%
Sep 30, 2025	INTECH INVESTMENT MANAGEMENT LLC	0.02%	7.49K	220.16K	7.49K	+100.00%
Sep 30, 2025	LEGAL & GENERAL GROUP PLC	0.02%	7.37K	217.2K	6K	+436.68%
Sep 30, 2025	VIRTUS INVESTMENT ADVISERS, INC.	0.02%	6.7K	196.99K	1.16K	+21.01%
Sep 30, 2025	MILLENNIUM MANAGEMENT LLC	0.49%	214.09K	6.3M	200.05K	+1,425.47%
Sep 30, 2025	ALYESKA INVESTMENT GROUP, L.P.	0.42%	186.22K	5.48M	0	0
Sep 30, 2025	RA CAPITAL MANAGEMENT, L.P.	23.68%	10.45M	307.2M	0	0
Sep 30, 2025	TPG GP A, LLC	15.29%	6.74M	198.37M	0	0
Sep 30, 2025	ORBIMED ADVISORS LLC	8.4%	3.7M	108.96M	0	0
Sep 30, 2025	ATLAS VENTURE LIFE SCIENCE ADVISORS, LLC	8.2%	3.62M	106.33M	-78.49K	-2.12%
Sep 30, 2025	JPMORGAN CHASE & CO	4.49%	1.98M	58.19M	-242.56K	-10.92%
Sep 30, 2025	NUVEEN, LLC	0.04%	16.04K	471.74K	0	0
Sep 30, 2025	DEUTSCHE BANK AG\	0.02%	9.6K	282.22K	0	0
Sep 30, 2025	JAIN GLOBAL LLC	0.02%	8.51K	250.37K	8.51K	+100.00%
Sep 30, 2025	METLIFE INVESTMENT MANAGEMENT, LLC	0.02%	8.03K	236.25K	0	0
Sep 30, 2025	BANK OF NEW YORK MELLON CORP	0.06%	27.46K	807.69K	3.33K	+13.81%
Sep 30, 2025	MORGAN STANLEY	0.05%	22.84K	671.64K	-21.18K	-48.12%
Sep 30, 2025	WELLS FARGO & COMPANY/MN	0.02%	7.58K	222.81K	1.2K	+18.86%
Sep 30, 2025	NEW YORK STATE COMMON RETIREMENT FUND	0.01%	5.3K	155.87K	-1.5K	-22.06%
Sep 30, 2025	CHINA UNIVERSAL ASSET MANAGEMENT CO., LTD.	0.01%	5K	147.05K	5K	+100.00%
Sep 30, 2025	POLICE & FIREMEN'S RETIREMENT SYSTEM OF NEW JERSEY	0.01%	3.23K	95.11K	626	+24.00%
Sep 30, 2025	BNP PARIBAS ARBITRAGE, SNC	0.01%	2.38K	70K	619	+35.15%
Sep 30, 2025	AMERITAS INVESTMENT PARTNERS, INC.	0%	1.26K	37.03K	0	0
Sep 30, 2025	RUSSELL INVESTMENTS GROUP, LTD.	0%	1.02K	30.06K	1.02K	+100.00%
Sep 30, 2025	CITIGROUP INC	0%	687	20.21K	-3.69K	-84.32%
Sep 30, 2025	AMALGAMATED BANK	0%	421	12K	0	0
Sep 30, 2025	ASTER CAPITAL MANAGEMENT (DIFC) LTD	0%	409	12.03K	409	+100.00%
Sep 30, 2025	FMR LLC	0%	234	6.88K	234	+100.00%
Sep 30, 2025	GAMMA INVESTING LLC	0%	153	4.5K	153	+100.00%
Sep 30, 2025	FEDERATED HERMES, INC.	0%	113	3.32K	113	+100.00%
Sep 30, 2025	US BANCORP \DE\	0%	111	3.27K	111	+100.00%
Sep 30, 2025	CWM, LLC	0%	60	2K	60	+100.00%
Sep 30, 2025	STERLING CAPITAL MANAGEMENT LLC	0%	30	882	0	0
Sep 30, 2025	EVERSOURCE WEALTH ADVISORS, LLC	0%	20	588	20	+100.00%
Sep 30, 2025	PNC FINANCIAL SERVICES GROUP, INC.	0%	5	147	5	+100.00%
Sep 30, 2025	COMMONWEALTH EQUITY SERVICES, LLC	0%	0	-	-14.02K	-100.00%
Sep 30, 2025	STRS OHIO	0%	0	-	-2.3K	-100.00%
Sep 30, 2025	PRUDENTIAL FINANCIAL INC	0%	0	-	-135.19K	-100.00%
Sep 30, 2025	OPTIONS SOLUTIONS, LLC	0%	0	-	-16.98K	-100.00%
Sep 30, 2025	BLACKROCK, INC.	1.91%	844.61K	24.84M	207.5K	+32.57%
Sep 30, 2025	PRICE T ROWE ASSOCIATES INC /MD/	1.45%	637.76K	18.76M	-223.48K	-25.95%
Sep 30, 2025	SOLEUS CAPITAL MANAGEMENT, L.P.	0.94%	413.5K	12.16M	37.5K	+9.97%
Sep 30, 2025	BAKER BROS. ADVISORS LP	0.91%	400K	11.76M	0	0
Sep 30, 2025	SIREN, L.L.C.	0.74%	325K	9.56M	0	0
Sep 30, 2025	RENAISSANCE TECHNOLOGIES LLC	0.03%	14.6K	429.39K	-11.4K	-43.85%
Sep 30, 2025	GOLDMAN SACHS GROUP INC	0.03%	12.18K	358.16K	-33.87K	-73.55%
Sep 30, 2025	SQUAREPOINT OPS LLC	0.02%	10.16K	298.86K	10.16K	+100.00%
Jun 30, 2025	SIREN, L.L.C.	0.74%	325K	5.64M	0	0
Jun 30, 2025	GEODE CAPITAL MANAGEMENT, LLC	0.66%	289.28K	5.02M	153.71K	+113.39%
Jun 30, 2025	AMERIPRISE FINANCIAL INC	0.54%	236.81K	4.11M	27.55K	+13.16%
Jun 30, 2025	ALYESKA INVESTMENT GROUP, L.P.	0.42%	186.22K	3.23M	0	0
Jun 30, 2025	SILVERARC CAPITAL MANAGEMENT, LLC	0.42%	186.02K	3.23M	71.88K	+62.97%
Jun 30, 2025	PRUDENTIAL FINANCIAL INC	0.31%	135.19K	2.35M	72.19K	+114.58%
Jun 30, 2025	STEMPOINT CAPITAL LP	0%	0	-	-60K	-100.00%
Jun 30, 2025	CENTERBOOK PARTNERS LP	0%	0	-	-114.28K	-100.00%
Jun 30, 2025	VIRTUS INVESTMENT ADVISERS, INC.	0.01%	5.54K	96.03K	5.54K	+100.00%
Jun 30, 2025	MIRAE ASSET GLOBAL ETFS HOLDINGS LTD.	0.02%	6.75K	117.06K	6.75K	+100.00%
Jun 30, 2025	VIKING GLOBAL INVESTORS LP	7.24%	3.2M	55.44M	242.43K	+8.21%
Jun 30, 2025	ATLAS VENTURE LIFE SCIENCE ADVISORS, LLC	8.37%	3.69M	64.09M	0	0
Jun 30, 2025	ORBIMED ADVISORS LLC	8.4%	3.7M	64.28M	0	0
Jun 30, 2025	TPG GP A, LLC	15.28%	6.74M	117.03M	60K	+0.90%
Jun 30, 2025	RA CAPITAL MANAGEMENT, L.P.	23.67%	10.45M	181.23M	0	0
Jun 30, 2025	SQUAREPOINT OPS LLC	0%	0	-	-33.96K	-100.00%
Jun 30, 2025		0.04%	16.04K	278.29K	16.04K	+100.00%
Jun 30, 2025	PERCEPTIVE ADVISORS LLC	2.76%	1.22M	21.1M	-35.06K	-2.80%
Jun 30, 2025	BRAIDWELL LP	2.45%	1.08M	18.77M	1.08M	+100.00%
Jun 30, 2025	DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C)	2.2%	970.59K	16.84M	223.59K	+29.93%
Jun 30, 2025	SUSQUEHANNA INTERNATIONAL GROUP, LLP	0.03%	14.83K	257.37K	14.83K	+100.00%
Jun 30, 2025	MILLENNIUM MANAGEMENT LLC	0.03%	14.03K	243.49K	-165.04K	-92.16%
Jun 30, 2025	COMMONWEALTH EQUITY SERVICES, LLC	0.03%	14.02K	243K	14.02K	+100.00%
Jun 30, 2025	DEUTSCHE BANK AG\	0.02%	9.6K	166.49K	9.6K	+100.00%
Jun 30, 2025	METLIFE INVESTMENT MANAGEMENT, LLC	0.02%	8.03K	139.37K	8.03K	+100.00%
Jun 30, 2025	NEW YORK STATE COMMON RETIREMENT FUND	0.02%	6.8K	117.98K	6.8K	+100.00%
Jun 30, 2025	JPMORGAN CHASE & CO	5.03%	2.22M	38.54M	51.59K	+2.38%
Jun 30, 2025	ABRDN PLC	2.15%	950.55K	16.49M	204.58K	+27.43%
Jun 30, 2025	JENNISON ASSOCIATES LLC	1.71%	752.8K	13.06M	-107.13K	-12.46%
Jun 30, 2025	BLACKROCK, INC.	1.44%	637.1K	11.05M	438.71K	+221.13%
Jun 30, 2025	BAKER BROS. ADVISORS LP	0.91%	400K	6.94M	0	0
Jun 30, 2025	SOLEUS CAPITAL MANAGEMENT, L.P.	0.85%	376K	6.52M	136K	+56.67%
Jun 30, 2025	ROCK SPRINGS CAPITAL MANAGEMENT LP	0.23%	99.43K	1.73M	0	0
Jun 30, 2025	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	0.21%	92.83K	1.61M	28.19K	+43.61%
Jun 30, 2025	NORTHERN TRUST CORP	0.21%	91.89K	1.59M	65.07K	+242.59%
Jun 30, 2025	DRIEHAUS CAPITAL MANAGEMENT LLC	0.19%	83.85K	1.45M	-245.04K	-74.51%
Jun 30, 2025	WOODLINE PARTNERS LP	0.18%	80K	1.39M	0	0
Jun 30, 2025	UBS GROUP AG	0.12%	51.37K	891.22K	40.22K	+360.86%
Jun 30, 2025	HOLOCENE ADVISORS, LP	0.11%	50K	867.5K	0	0
Jun 30, 2025	TD ASSET MANAGEMENT INC	0.11%	49.97K	866.91K	-5.4K	-9.75%
Jun 30, 2025	GOLDMAN SACHS GROUP INC	0.1%	46.05K	798.93K	-17.69K	-27.76%
Jun 30, 2025	MORGAN STANLEY	0.1%	44.02K	763.71K	40.08K	+1,017.49%
Jun 30, 2025	MANUFACTURERS LIFE INSURANCE COMPANY, THE	0.09%	38.04K	659.96K	4.49K	+13.38%
Jun 30, 2025	ENAVATE SCIENCES GP, LLC	5.62%	2.48M	42.99M	0	0
Jun 30, 2025	CITADEL ADVISORS LLC	0.29%	129.91K	2.25M	-196.59K	-60.21%
Jun 30, 2025	STATE STREET CORP	0.28%	124.52K	2.16M	110.12K	+764.71%
Jun 30, 2025	RENAISSANCE TECHNOLOGIES LLC	0.06%	26K	451.1K	26K	+100.00%
Jun 30, 2025	BANK OF NEW YORK MELLON CORP	0.05%	24.13K	418.67K	24.13K	+100.00%
Jun 30, 2025	NUVEEN, LLC	0.04%	16.04K	278.29K	16.04K	+100.00%
Jun 30, 2025	PRICE T ROWE ASSOCIATES INC /MD/	1.95%	861.24K	14.94M	-134.97K	-13.55%
Jun 30, 2025	VANGUARD GROUP INC	1.43%	630.35K	10.94M	84.18K	+15.41%
Jun 30, 2025	FRANKLIN RESOURCES INC	1.13%	500.02K	8.68M	0	0
Jun 30, 2025	ROYAL BANK OF CANADA	0%	60	1K	-558	-90.29%
Jun 30, 2025	CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM	0%	770	13.36M	770	+100.00%
Jun 30, 2025	BNP PARIBAS ARBITRAGE, SNC	0%	1.76K	30.55M	1.76K	+100.00%
Jun 30, 2025	POLEN CAPITAL MANAGEMENT LLC	0.04%	16.98K	294.52K	16.98K	+100.00%
Jun 30, 2025	OPTIONS SOLUTIONS, LLC	0.04%	16.98K	294.52K	16.98K	+100.00%
Jun 30, 2025	RHUMBLINE ADVISERS	0.04%	17.67K	306.57K	17.67K	+100.00%
Jun 30, 2025	BARCLAYS PLC	0.05%	23.02K	400K	23.02K	+100.00%
Jun 30, 2025	STERLING CAPITAL MANAGEMENT LLC	0%	30	521	30	+100.00%
Jun 30, 2025	TWO SIGMA INVESTMENTS, LP	0%	0	-	-11.72K	-100.00%
Jun 30, 2025	BALYASNY ASSET MANAGEMENT L.P.	0%	0	-	-13.06K	-100.00%
Jun 30, 2025	MARSHALL WACE, LLP	0%	0	-	-12.19K	-100.00%
Jun 30, 2025	ZIMMER PARTNERS, LP	0%	0	-	-237.5K	-100.00%
Mar 31, 2025	DRIEHAUS CAPITAL MANAGEMENT LLC	1.24%	328.89K	3.44M	328.89K	+100.00%
Mar 31, 2025	BAKER BROS. ADVISORS LP	1.5%	400K	4.18M	400K	+100.00%
Mar 31, 2025	FRANKLIN RESOURCES INC	1.88%	500.02K	5.23M	500.02K	+100.00%
Mar 31, 2025		0.06%	14.76K	203.2K	14.76K	+100.00%
Mar 31, 2025	ATLAS VENTURE LIFE SCIENCE ADVISORS, LLC	13.89%	3.69M	38.64M	3.69M	+100.00%
Mar 31, 2025	JPMORGAN CHASE & CO	8.16%	2.17M	22.69M	2.17M	+100.00%
Mar 31, 2025	RA CAPITAL MANAGEMENT, L.P.	39.27%	10.45M	109.26M	10.45M	+100.00%
Mar 31, 2025	STEMPOINT CAPITAL LP	0.23%	60K	627.6K	60K	+100.00%
Mar 31, 2025	AMERIPRISE FINANCIAL INC	0.79%	209.27K	2.19M	209.27K	+100.00%
Mar 31, 2025	VANGUARD GROUP INC	2.05%	546.17K	5.71M	546.17K	+100.00%
Mar 31, 2025	ABRDN PLC	2.8%	745.96K	7.8M	745.96K	+100.00%
Mar 31, 2025	DEERFIELD MANAGEMENT COMPANY, L.P. (SERIES C)	2.81%	747K	7.81M	747K	+100.00%
Mar 31, 2025	ROCK SPRINGS CAPITAL MANAGEMENT LP	0.37%	99.43K	1.04M	99.43K	+100.00%
Mar 31, 2025	NORTHERN TRUST CORP	0.1%	26.82K	280.56K	26.82K	+100.00%
Mar 31, 2025	MANUFACTURERS LIFE INSURANCE COMPANY, THE	0.13%	33.55K	350.92K	33.55K	+100.00%
Mar 31, 2025	SQUAREPOINT OPS LLC	0.13%	33.96K	355.26K	33.96K	+100.00%
Mar 31, 2025	TD ASSET MANAGEMENT INC	0.21%	55.37K	579.13K	55.37K	+100.00%
Mar 31, 2025	CITADEL ADVISORS LLC	1.23%	326.5K	3.42M	326.5K	+100.00%
Mar 31, 2025	ROYAL BANK OF CANADA	0%	618	6K	618	+100.00%
Mar 31, 2025	MORGAN STANLEY	0.01%	3.94K	41.2K	3.94K	+100.00%
Mar 31, 2025	BANK OF AMERICA CORP /DE/	0.03%	8.74K	91.41K	8.74K	+100.00%
Mar 31, 2025	UBS GROUP AG	0.04%	11.15K	116.59K	11.15K	+100.00%
Mar 31, 2025	WOODLINE PARTNERS LP	0.3%	80K	836.8K	80K	+100.00%
Mar 31, 2025	SOLEUS CAPITAL MANAGEMENT, L.P.	0.9%	240K	2.51M	240K	+100.00%
Mar 31, 2025	VIKING GLOBAL INVESTORS LP	11.1%	2.95M	30.89M	2.95M	+100.00%
Mar 31, 2025	STATE STREET CORP	0.05%	14.4K	150.62K	14.4K	+100.00%
Mar 31, 2025	SILVERARC CAPITAL MANAGEMENT, LLC	0.43%	114.14K	1.19M	114.14K	+100.00%
Mar 31, 2025	TWO SIGMA INVESTMENTS, LP	0.04%	11.72K	122.54K	11.72K	+100.00%
Mar 31, 2025	MARSHALL WACE, LLP	0.05%	12.19K	127.49K	12.19K	+100.00%
Mar 31, 2025	BALYASNY ASSET MANAGEMENT L.P.	0.05%	13.06K	136.61K	13.06K	+100.00%
Mar 31, 2025	HOLOCENE ADVISORS, LP	0.19%	50K	523K	50K	+100.00%
Mar 31, 2025	CENTERBOOK PARTNERS LP	0.43%	114.28K	1.2M	114.28K	+100.00%
Mar 31, 2025	MILLENNIUM MANAGEMENT LLC	0.67%	179.07K	1.87M	179.07K	+100.00%
Mar 31, 2025	ALYESKA INVESTMENT GROUP, L.P.	0.7%	186.22K	1.95M	186.22K	+100.00%
Mar 31, 2025	BLACKROCK, INC.	0.75%	198.4K	2.08M	198.4K	+100.00%
Mar 31, 2025	ORBIMED ADVISORS LLC	13.93%	3.7M	38.75M	3.7M	+100.00%
Mar 31, 2025	TPG GP A, LLC	25.14%	6.68M	69.92M	6.68M	+100.00%
Mar 31, 2025	GOLDMAN SACHS GROUP INC	0.24%	63.74K	666.73K	63.74K	+100.00%
Mar 31, 2025	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	0.24%	64.64K	676.18K	64.64K	+100.00%
Mar 31, 2025	GEODE CAPITAL MANAGEMENT, LLC	0.51%	135.56K	1.42M	135.56K	+100.00%
Mar 31, 2025	ZIMMER PARTNERS, LP	0.89%	237.5K	2.48M	237.5K	+100.00%
Mar 31, 2025	SIREN, L.L.C.	1.22%	325K	3.4M	325K	+100.00%
Mar 31, 2025	JENNISON ASSOCIATES LLC	3.23%	859.93K	8.99M	859.93K	+100.00%
Mar 31, 2025	PRICE T ROWE ASSOCIATES INC /MD/	3.75%	996.21K	10.42M	996.21K	+100.00%
Mar 31, 2025	PERCEPTIVE ADVISORS LLC	4.7%	1.25M	13.09M	1.25M	+100.00%
Mar 31, 2025	PRUDENTIAL FINANCIAL INC	0.24%	63K	658.98K	63K	+100.00%

Insiders

Among the SION insiders holding of 6.93% of the stake in company, TPG GP A, LLC, 10 percent owner, holds the largest shares of 6.49M. THOMPSON PETER A., director, is the second largest SION insider with ownership of 3.53M shares. ORBIMED ADVISORS LLC, director, stands third with possession of 3.53M shares of that stake.

Insiders	Designation	Shares Held
TPG GP A, LLC	10 percent owner	6.49M
THOMPSON PETER A.	director	3.53M
ORBIMED ADVISORS LLC	director	3.53M
BOOTH BRUCE	director	686.57K
CLOONAN MICHAEL	President & CEO	547.34K
RA CAPITAL MANAGEMENT, L.P.		159.03K
RIDLOFF ELENA	CFO & Head of Corp. Dev.	38.53K
FITZPATRICK JENNIFER	Chief Legal Officer	0

Buying/Selling by Insiders

Date	Insider	Type	Cost	Shares	Value ($)	Shares Total
Feb 03, 2026	THOMPSON PETER A.	SALE	44.58	29.06K	1.3M	3.53M
Feb 03, 2026	ORBIMED ADVISORS LLC	SALE	44.58	29.06K	1.3M	3.53M
Feb 02, 2026	ORBIMED ADVISORS LLC	SALE	44.57	1.89K	84.24K	3.56M
Feb 02, 2026	THOMPSON PETER A.	SALE	44.57	1.89K	84.24K	3.56M
Jan 22, 2026	TPG GP A, LLC	SALE	40.00	250K	10M	6.49M
Dec 24, 2025	ORBIMED ADVISORS LLC	SALE	44.55	33.36K	1.49M	3.56M
Dec 24, 2025	THOMPSON PETER A.	SALE	44.55	33.36K	1.49M	3.56M
Dec 19, 2025	THOMPSON PETER A.	SALE	44.49	875	38.93K	3.6M
Dec 19, 2025	ORBIMED ADVISORS LLC	SALE	44.49	875	38.93K	3.6M
Dec 18, 2025	ORBIMED ADVISORS LLC	SALE	44.49	100	4.45K	3.6M
Dec 18, 2025	THOMPSON PETER A.	SALE	44.49	100	4.45K	3.6M
Dec 17, 2025	ORBIMED ADVISORS LLC	SALE	44.50	900	40.05K	3.6M
Dec 17, 2025	THOMPSON PETER A.	SALE	44.50	900	40.05K	3.6M
Dec 05, 2025	FITZPATRICK JENNIFER	SALE	40.52	10.25K	415.33K	0
Nov 26, 2025	ORBIMED ADVISORS LLC	SALE	44.49	1.6K	71.18K	3.6M
Nov 26, 2025	THOMPSON PETER A.	SALE	44.49	1.6K	71.18K	3.6M
Nov 25, 2025	THOMPSON PETER A.	SALE	44.60	11.89K	530.29K	3.6M
Nov 25, 2025	ORBIMED ADVISORS LLC	SALE	44.60	11.89K	530.29K	3.6M
Nov 24, 2025	ORBIMED ADVISORS LLC	SALE	44.54	94.58K	4.21M	3.61M
Nov 24, 2025	THOMPSON PETER A.	SALE	44.54	94.58K	4.21M	3.61M
Nov 21, 2025	RA CAPITAL MANAGEMENT, L.P.	SALE	39.50	7.61K	300.56K	159.03K
Nov 20, 2025	RA CAPITAL MANAGEMENT, L.P.	SALE	40.50	604	24.46K	166.64K
Nov 19, 2025	RA CAPITAL MANAGEMENT, L.P.	SALE	40.61	9	365.49	168.19K
Nov 18, 2025	RA CAPITAL MANAGEMENT, L.P.	SALE	39.57	2.09K	82.78K	182.53K
Nov 17, 2025	RA CAPITAL MANAGEMENT, L.P.	SALE	42.10	331	13.94K	184.62K
Oct 28, 2025	RA CAPITAL MANAGEMENT, L.P.	SALE	39.58	10.48K	414.64K	209.39K
Oct 24, 2025	RA CAPITAL MANAGEMENT, L.P.	SALE	39.50	107.94K	4.26M	219.87K
Oct 21, 2025	BOOTH BRUCE	SALE	36.42	17	619.14	686.57K
Oct 21, 2025	CLOONAN MICHAEL	SALE	36.60	22.9K	837.96K	547.34K
Oct 20, 2025	BOOTH BRUCE	SALE	32.33	5.41K	174.97K	701.99K
Oct 17, 2025	BOOTH BRUCE	SALE	33.47	52	1.74K	711.7K
Oct 16, 2025	CLOONAN MICHAEL	SALE	34.00	200	6.8K	547.34K
Oct 16, 2025	BOOTH BRUCE	SALE	33.38	2.71K	90.29K	722.3K
Oct 15, 2025	BOOTH BRUCE	SALE	31.12	6.3K	196.15K	751.66K
Oct 15, 2025	CLOONAN MICHAEL	SALE	31.11	14.78K	459.66K	547.34K
Oct 14, 2025	BOOTH BRUCE	SALE	29.95	105	3.14K	771.76K
Oct 13, 2025	BOOTH BRUCE	SALE	31.03	857	26.59K	771.87K
Oct 10, 2025	BOOTH BRUCE	SALE	29.98	3.51K	105.26K	781.97K
Oct 06, 2025	BOOTH BRUCE	SALE	29.95	2.05K	61.31K	785.48K
Oct 03, 2025	BOOTH BRUCE	SALE	30.00	6.55K	196.44K	787.53K
Oct 01, 2025	BOOTH BRUCE	SALE	29.95	35	1.05K	794.08K
Sep 30, 2025	BOOTH BRUCE	SALE	30.06	2.15K	64.6K	794.11K
Sep 29, 2025	CLOONAN MICHAEL	SALE	29.70	7.79K	231.45K	547.34K
Sep 29, 2025	BOOTH BRUCE	SALE	30.09	11.47K	345.07K	796.26K
Sep 26, 2025	CLOONAN MICHAEL	SALE	28.85	17.21K	496.35K	547.34K
Sep 04, 2025	FITZPATRICK JENNIFER	SALE	23.12	10.25K	236.98K	0
Sep 02, 2025	RIDLOFF ELENA	SALE	25.08	8.84K	221.61K	38.53K
Aug 29, 2025	RIDLOFF ELENA	SALE	25.18	748	18.83K	47.37K
Aug 28, 2025	RIDLOFF ELENA	SALE	25.97	16.1K	418.07K	48.12K
Aug 27, 2025	RIDLOFF ELENA	SALE	25.10	3.62K	90.81K	64.21K
Aug 27, 2025	CLOONAN MICHAEL	SALE	25.01	7.43K	185.71K	547.34K
Aug 26, 2025	CLOONAN MICHAEL	SALE	24.96	17.57K	438.65K	547.34K
Aug 26, 2025	RIDLOFF ELENA	SALE	25.13	3.7K	92.98K	67.83K
Aug 20, 2025	RIDLOFF ELENA	SALE	22.69	17.5K	397.08K	71.53K
Aug 20, 2025	CLOONAN MICHAEL	SALE	22.75	25K	568.75K	547.34K
Aug 19, 2025	RIDLOFF ELENA	SALE	21.08	34.5K	727.26K	89.03K
Jun 27, 2025	TPG GP A, LLC	PURCHASE	15.84	60K	950.4K	6.74M

Insider Transaction Summary (6 Months)

SHARESTRANS

PURCHASE00

SALES852.16K46

NET SHARES-852.16K46

SHARES HELD84.87M46

% NET SHARES-101%0%

Frequently Asked Questions