Entity type
Company
Filer Snapshot
ARDSLEY ADVISORY PARTNERS LP
CIK 0000900529. SEC filing timeline plus parsed ownership intelligence from 13F, 13D/G, and Forms 3/4/5 where available.
Total filings
54
Latest filing
15 May 2026
Industry
n/a
Filing-backed research brief
Start with the SEC data that changes for this CIK
Latest signal: 13F-HR for Q1 2026. Each card links back to the PortfolioSavvy page where the filing evidence is closest.
Latest 13F portfolio
$656.41M
117 holdings for Q1 2026
Open portfolioLargest parsed holding
UTHR
$29.65M reported value
Open holding13D/G large stake
ASBP
31 Dec 2025 · 0% ownership
Open 13D/GInsider / owner context
MBII
11 Nov 2021 · $14.67M
Open owner pageSave this filer page
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Source: SEC Form 13F
View source filing
13F-HR filed on 15 May 2026 for CIK 0000900529.
- Ownership evidence
-
SEC filing family snapshot
These bars compare visible SEC-reported value by filing family. They should be read side by side, not added into one ownership total.
Latest 13F portfolio$656.41MQuarterly institutional holdings reported on Form 13F.
Forms 3/4/5 positions$14.67MReporting-owner positions with enough filing detail to estimate value.
Latest 13F portfolio value
13F$656.41MMarket value reported in the latest parsed Form 13F information table; this is not total AUM.
Estimated owner position value
3/4/5$14.67MEstimated from parsed Forms 3/4/5 when the filing includes enough shares and price data.
Largest 13F positions
13FUTHR AVGO SNDK AMZN ANET+15 more
SMTC MOD SEZL TEVA META RUN NVDA WULF BTSG SHLS VIAV EBAY AMLP NU BSXLargest symbols in the latest parsed Form 13F information table.
Largest linked issuer positions
Largest issuer positions linked to this CIK across parsed 13F, 13D/G, and Forms 3/4/5 records.
MBIILargest 13F positions
Largest symbols in the latest parsed Form 13F information table.
UTHR AVGO SNDK AMZN ANET SMTC MOD SEZL+12 more
TEVA META RUN NVDA WULF BTSG SHLS VIAV EBAY AMLP NU BSXSchedule 13G positions
Passive or institutional large-stake positions disclosed in parsed Schedule 13G filings.
ASBPHow to read this ownership snapshot
- Read each filing family separately: 13F portfolios, 13D/G large stakes, and Forms 3/4/5 owner positions are different SEC disclosure regimes.
- Open the linked research path when you need the filing behind a value.
- Business address
- 105 Rowayton Ave, Norwalk, CT, 06853
- State of incorporation
- NY
- Fiscal year-end
- 31 December
- Former SEC names
- ARDSLEY ADVISORY PARTNERS (to 14 Nov 2018)
Ownership signals
CIK-linked ownership evidence from parsed SEC filings.
1 signal
Identity
Who this page is about.
1 identity field
SEC profile Static EDGAR profile fields. 3 profile fields
Filer intelligence
What SEC filings say about ARDSLEY ADVISORY PARTNERS LP
A compact read of parsed XML filings. 13F, 13D/G, and Forms 3/4/5 are shown separately because they answer different ownership questions.
Quick read
- Latest parsed 13F shows $656.41M across 117 reported holdings for Q1 2026.
- Largest parsed 13F holding: UTHR at $29.65M.
- 1 recent 13D/G stake row found; top row is ASBP at 0% ownership.
- Forms 3/4/5 show insider context for MBII worth $14.67M.
SEC source mix
Counts show available parsed rows, not one combined ownership total.
Top parsed 13F holdings
Visual share of the latest parsed 13F portfolio. Values are reported market value, not a recommendation.
Top 5 concentration
19%
Share of latest parsed 13F value represented by the visible holdings below.
Top 5 reported value
$127.48M
Compared with $656.41M total 13F value.
Top 5 net change
+$42.33M
Position-value change inside the visible top holdings only.
13F concentration map
A simple visual split of the latest parsed 13F portfolio.
Largest add: UTHR · Largest trim: LITE
UTHR
AVGO
SNDK
AMZN
ANET
Other holdings
13D/G large-stake context
ASBP
31 Dec 2025 · Common Stock
Forms 3/4/5 insider context
MBII
11 Nov 2021 · 10% owner
Latest update
What changed recently for ARDSLEY ADVISORY PARTNERS LP
Latest 13F period: Q1 2026. Open the source-backed page to inspect the fresh filing or facts context.
Update date
15 May 2026
Page type
Filer profile
Latest period
Q1 2026
Institutional portfolio context was refreshed from a 13F filing filed on 15 May 2026.
Benchmark Context
Benchmark context for this company
ARDSLEY ADVISORY PARTNERS LP has a source-backed company facts view where you can compare the latest reported metrics with its own recent history and with peer rankings for the same metric.
Compared with
Start on the facts page for period-to-period context, then open a metric ranking when you want to compare the same reported fact across other SEC-reporting companies.
Why this is notable
Latest 13F period: Q1 2026. That gives you a fresh baseline before you compare this company with peers.
- Peer comparisons stay conservative: same metric, compatible units, latest valid company row only.
- Open the facts page first if you want the cleanest path to verification.
Benchmark context is only shown where the app has enough comparable SEC-backed data to keep the interpretation honest.
SEC filing record
CIK 0000900529 filing coverage
Start with this filing record, then use the linked ownership pages when parsed 13F, 13D/G, Forms 3/4/5, or facts data exists for this CIK.
SEC filings
54
First seen
12 Feb 2014
Latest filing
15 May 2026
Entity
Company
Observed form types
13F-HR
13F-HR/A
SCHEDULE 13G
SCHEDULE 13G/A
Latest Filings
Showing the latest 12 of 54 SEC filings for ARDSLEY ADVISORY PARTNERS LP.
13F-HR
13F-HR filing
- Filing date
- 15 May 2026
- Reporting date
- 31 Mar 2026
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
SCHEDULE 13G/A
SCHEDULE 13G/A filing
- Filing date
- 13 May 2026
- Reporting date
- Not listed
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 17 Feb 2026
- Reporting date
- 31 Dec 2025
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
SCHEDULE 13G
SCHEDULE 13G filing
- Filing date
- 12 Feb 2026
- Reporting date
- Not listed
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 14 Nov 2025
- Reporting date
- 30 Sep 2025
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 14 Aug 2025
- Reporting date
- 30 Jun 2025
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 15 May 2025
- Reporting date
- 31 Mar 2025
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 14 Feb 2025
- Reporting date
- 31 Dec 2024
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 14 Nov 2024
- Reporting date
- 30 Sep 2024
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 14 Aug 2024
- Reporting date
- 30 Jun 2024
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 15 May 2024
- Reporting date
- 31 Mar 2024
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing
13F-HR
13F-HR filing
- Filing date
- 14 Feb 2024
- Reporting date
- 31 Dec 2023
- SEC evidence
- Open document Open filing
- Next action
- Verify source filing