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ARDSLEY ADVISORY PARTNERS LP

SEC Form 13F institutional filer · CIK 0000900529

13F-HR · 40 reported holdings · 2026-03-31

Reported long-US-equity value

$0.29B

Top-10 concentration

61.1%

ARDSLEY ADVISORY PARTNERS LP — $286M AUM allocation strategy

ARDSLEY ADVISORY PARTNERS LP files SEC Form 13F and reports $286M of long US equity value across 40 reported holdings for 2026-03-31.

Its largest sector bet is Information Technology 40.9%, followed by Consumer Discretionary 12.2% and Communication Services 10.9%.

The top 10 holdings account for 61% of reported value — a conviction-weighted book concentrated in its best ideas. The sector and industry splits below are of the same reported value. Track quarter-over-quarter adds, trims, new positions and exits below — sourced from SEC 13F filings, public domain.

ARDSLEY ADVISORY PARTNERS LP — latest SEC 13F insights

Reported long-US-equity value (13F AUM)

$286M

total across 40 reported holdings · 2026-03-31 · excludes shorts, cash, non-US

Top-10 concentration

61% of value

higher = narrower conviction; lower = spread / hedging

Biggest adds (shares)

$ANET$NOW$EBAY

+$ANET +73.7K sh · +$8.22M+$NOW +60.6K sh · +$5.77M+$EBAY +55.5K sh · +$5.38M

Biggest trims (shares)

$AMAT$LITE$TXN

−$AMAT −535K sh · +$4.88M−$LITE −73.8K sh · −$25.1M−$TXN −54K sh · −$9.24M

Added from nil (new positions)

$BSX$EQIX$VZ$ADI$MU

5 fresh holdings — new conviction

Exited to nil (held last quarter, gone now)

$FSLR$TEL$BLK$CRM$PANW

$FSLR ($30.7M last qtr)$TEL ($16.7M last qtr)$BLK ($9.79M last qtr)$CRM ($8.73M last qtr)$PANW ($7.37M last qtr)

Sector allocation (share of reported value)

Information Technology 41%Consumer Discretionary 12%Communication Services 11%Health Care 5%Financials 5%Real Estate 3%Materials 2%ETFs 2%Other holdings 18%SECTORS
  • $XLKInformation Technology40.9%
  • $XLYConsumer Discretionary12.2%
  • $XLCCommunication Services10.9%
  • $XLVHealth Care5.5%
  • $XLFFinancials5.2%
  • $XLREReal Estate2.7%
  • $XLBMaterials2.4%
  • ETFs2.4%
  • Other holdings17.9%

each slice is a share of the reported long-US-equity value — smaller sectors and the rest of the book roll into “Other holdings”

Qtr shift = share-point change vs the prior quarter's filing — first period tracked for this filer; the column fills in with the next quarterly refresh.

Industry allocation (share of reported value)

Semiconductors 18%Broadline Retail 12%Technology Hardware, Storage & Peripherals 9%Interactive Media & Services 9%Communications Equipment 7%Asset Management & Custody Banks 5%Health Care Equipment 3%Semiconductor Materials & Equipment 3%Other holdings 32%INDUSTRIES
  • Semiconductors18.5%
  • Broadline Retail12.2%
  • Technology Hardware, Storage & Peripherals9.3%
  • Interactive Media & Services8.6%
  • Communications Equipment7.5%
  • Asset Management & Custody Banks5.2%
  • Health Care Equipment3.3%
  • Semiconductor Materials & Equipment3.0%
  • Other holdings32.5%

the finer GICS cut of the same book — same denominator — smaller industries roll into “Other holdings”

Qtr shift = share-point change vs the prior quarter's filing — first period tracked for this filer; the column fills in with the next quarterly refresh.

Top S&P 500 holdings

10 of 10 rows · sorted by Value ↓

TickerHoldingSharesValueΔ QoQWeight
$AVGOBroadcom Inc89.5K$27.7M+5.5K9.7%
$SNDKSandisk Corporation42K$26.7M-14K9.3%
$AMZNAmazon.com Inc106K$22.1M+52K7.7%
$ANETArista Networks Inc174K$21.3M+73.7K7.5%
$METAMeta Platforms Inc28K$16M+26K5.6%
$NVDANVIDIA Corporation87.5K$15.3M-37.5K5.3%
$KKRKKR & Co. Inc350K$14.9M+05.2%
$EBAYeBay Inc141K$12.8M+55.5K4.5%
$BSXBoston Scientific Corporation150K$9.41M3.3%
$GOOGLAlphabet Inc30K$8.61M-27K3.0%

…and 30 more holdings in the full 13F filing (top positions only shown).

SEC Form 13F data sets · public domain · 45-day filing lag · >$100M AUM managers · as reported

← All 13F filers·← QuantOrb.pro

How to read Δ QoQ — the five insight categories, and the caveats

The categories. Analysts, quants and retail traders look past total portfolio value to isolate actionable signals. Five categories matter.

Conviction & concentration shifts

New positions vs complete exits — a brand-new stock signals high conviction; a full liquidation suggests a broken thesis or tax-loss harvesting. Aggressive sizing — look at share count, not dollars: a 20% share increase during a drawdown is strong dip-buying. Concentration — a narrowing top-5/10 means conviction; spreading capital across more names means hedging.

Sector & macro allocation rotations

Aggregating Δ QoQ moves across sectors shows where smart money is leaning in or sneaking out — rotating out of growth into defensives or energy, for example. The fund's total long equity exposure quarter-over-quarter is a proxy for overall institutional risk appetite.

Crowding & smart-money consensus

When several managers initiate or expand the same stock in the same quarter, that is institutional consensus. Contrarian reads: top pickers buying hard into a beaten-down name the market is selling.

Derivative & option overlays

Reported call/put changes indicate whether managers are adding downside hedges or leveraging upside exposure. Note: a long increase may be half of a market-neutral pair trade.

Who reads this

Retail "cloners"High-conviction ideas to replicate ~45 days after quarter-end.
Corporate IRWhich funds bought or dumped the stock, before the next call.
Quant / algo tradersCross-sectional factor inputs: flow, momentum, ownership.

Four caveats before you trade on it

  • 45-day lag — holdings are quarter-end; positions may already be closed.
  • Long-only — 13Fs miss shorts, pair trades and cash.
  • No non-US / fixed income — the picture is US equities plus options.
  • Corporate actions — splits and spinoffs distort raw share deltas.

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