SEC 13F Intelligence

Managers / Q1 2019 · view latest →

Palo Alto Investors LP

CIK 0001306923 · 101 UNIVERSITY AVE, SUITE 200, PALO ALTO, CA, 94301 · 650-325-0772

Reported Value
$2.4B
Q1 2019
Positions
37
Filings on Record
33
2019–present window
Filed
May 15, 2019
original filing

Summary

Palo Alto Investors LP reported $2.4B in U.S.-listed holdings across 37 positions for Q1 2019.

Its largest position, BMRN, represents 9.8% of the portfolio.

Compared with Q4 2018, the fund opened 4 new positions and exited 3.

Portfolio Metrics

Turnover
+5.2%
vs prior filed quarter
Top-10 Concentration
+68.9%
share of reported value
Largest Position
+9.8%
Biomarin Pharmaceutical
New / Exited
4 / 3
positions this quarter

Methodology: turnover is min(value bought, value sold) ÷ average reported value across the two quarters — value-based, so market moves inflate it slightly versus a share-based measure. Concentration and largest position are shares of the filing’s total reported value, options excluded. New/exited counts compare against the prior filed quarter. All figures derive solely from the fund’s 13F filings.

Reported Value by Quarter

13F Reported Value
Q4 ’18: $1.9BQ4 ’18Q1 ’19: $2.4BQ2 ’19: $2.1BQ3 ’19: $1.5BQ4 ’19: $1.8BQ4 ’19Q1 ’20: $1.2BQ2 ’20: $1.7BQ3 ’20: $1.8BQ4 ’20: $1.9BQ4 ’20Q1 ’21: $1.8BQ2 ’21: $1.8BQ3 ’21: $1.7BQ4 ’21: $1.6BQ4 ’21Q1 ’22: $1.3BQ2 ’22: $1.1BQ3 ’22: $1.3BQ4 ’22: $1.2BQ4 ’22Q1 ’23: $1.2BQ2 ’23: $1.2BQ3 ’23: $1.1BQ4 ’23: $1.1BQ4 ’23Q1 ’24: $887MQ2 ’24: $863MQ3 ’24: $770MQ4 ’24: $645MQ4 ’24Q1 ’25: $525MQ2 ’25: $470MQ3 ’25: $540MQ4 ’25: $718MQ4 ’25Q1 ’26: $654Mfilingsflow.com

Portfolio Composition

By security type
Common Stock: 95.8%Other: 4.2%
  • Common Stock · 95.8% · $2.3B
  • Other · 4.2% · $101M

Quarter-over-Quarter Changes full breakdown →

vs Q4 2018 (amended baseline)

IssuerMoveShare ΔShares nowValue ΔValue now
ACHCACADIA HEALTHCARE COMPANY INNEW+2.25M2.25M+$60M$60M
KLDOKALEIDO BIOSCIENCES INCNEW+866.7K866.7K+$13M$13M
MRNSUSDMARINUS PHARMACEUTICALS INCNEW+114.2K114.2K+$477,000$477,000
CEMPEURMELINTA THERAPEUTICS INCNEW+10.1K10.1K+$36,000$36,000
AIMTAIMMUNE THERAPEUTICS INCADDED+2.36M3.75M+$51M$84M
ACADACADIA PHARMACEUTICALS INCSOLD OUT−2.03M0−$33M$0
SHIRE PLCSOLD OUT−47.9K0−$8M$0
MELINTA THERAPEUTICS INCSOLD OUT−50.7K0−$40,000$0

Value changes conflate price moves with buying and selling — share changes are the real signal. Share counts are not split-adjusted.

Holdings — Q1 2019

37 positions
Export to Excel
#IssuerClass% PortfolioValue ↓Shares
1BMRNBIOMARIN PHARMACEUTICAL INChistory →COM9.79%$235M2.64M
2IM8NINSMED INChistory →COM PAR $.019.28%$222M7.65M
3ABMDEURABIOMED INChistory →COM8.32%$200M698.7K
4UTHUNITED THERAPEUTICS CORP DELhistory →COM7.99%$192M1.63M
5ALXNALEXION PHARMACEUTICALS INChistory →COM6.93%$166M1.23M
6STAASTAAR SURGICAL COhistory →COM PAR $0.016.02%$144M4.22M
7SG7SAGE THERAPEUTICS INChistory →COM5.69%$136M857.7K
8CLVSEURCLOVIS ONCOLOGY INChistory →COM5.43%$130M5.24M
9IMMUIMMUNOMEDICS INChistory →COM5.11%$123M6.38M
10AM6AMICUS THERAPEUTICS INChistory →COM4.32%$104M7.62M
11VNDAVANDA PHARMACEUTICALS INChistory →COM3.88%$93M5.06M
12WRIGHT MED GROUP N VORD SHS3.64%$87M2.77M
13EPZMEUREPIZYME INChistory →COM3.58%$86M6.94M
14AIMTAIMMUNE THERAPEUTICS INChistory →COM3.50%$84M3.75M
15ACHCACADIA HEALTHCARE COMPANY INhistory →COM2.52%$60M2.25M
16AFWALIGN TECHNOLOGY INChistory →COM1.96%$47M165.4K
17PBYIPUMA BIOTECHNOLOGY INChistory →COM1.91%$46M1.18M
18AMAGAMAG PHARMACEUTICALS INChistory →COM1.84%$44M3.42M
19KPTIEURKARYOPHARM THERAPEUTICS INChistory →COM1.28%$31M5.26M
20EXKEXACT SCIENCES CORPhistory →COM1.14%$27M314.9K
21MNTAMOMENTA PHARMACEUTICALS INChistory →COM1.12%$27M1.84M
22ALDR1EURALDER BIOPHARMACEUTICALS INChistory →COM1.06%$25M1.86M
23CELGCELGENE CORPhistory →COM1.05%$25M266.3K
24PROTHENA CORP PLCSHS0.56%$13M1.11M
25KLDOKALEIDO BIOSCIENCES INChistory →COM0.52%$13M866.7K
26GILDGILEAD SCIENCES INChistory →COM0.48%$11M175.9K
27RIGLUSDRIGEL PHARMACEUTICALS INChistory →COM NEW0.43%$10M3.99M
28DRNAUSDDICERNA PHARMACEUTICALS INCCOM0.31%$7M500.9K
29ALIMEURALIMERA SCIENCES INCCOM0.13%$3M3.01M
30ZGNXEURZOGENIX INCCOM NEW0.07%$2M29.5K
31SNSSUSDSUNESIS PHARMACEUTICALS INCCOM PAR0.06%$1M1.16M
32CYTKCYTOKINETICS INCCOM NEW0.04%$1M123.7K
33MRNSUSDMARINUS PHARMACEUTICALS INCCOM0.02%$477,000114.2K
34SPHSEURSOPHIRIS BIO INCCOM NEW0.01%$245,000247.0K
35IDERA PHARMACEUTICALS INCCOM PAR0.01%$196,00077.0K
36CEMPEURMELINTA THERAPEUTICS INCCOM NEW0.00%$36,00010.1K
37HISTOGENICS CORPCOM0.00%$35,000302.9K

Filing History

QuarterReported ValuePositionsFiledTypeLinks
Q1 2026$654M51May 15, 202613F-HRchanges · EDGAR ↗
Q4 2025$718M49Feb 17, 202613F-HRchanges · EDGAR ↗
Q3 2025$540M44Nov 14, 202513F-HRchanges · EDGAR ↗
Q2 2025$470M45Aug 14, 202513F-HRchanges · EDGAR ↗
Q1 2025$525M44May 15, 202513F-HRchanges · EDGAR ↗
Q4 2024$645M43Feb 14, 202513F-HRchanges · EDGAR ↗
Q3 2024$770M45Nov 14, 202413F-HRchanges · EDGAR ↗
Q2 2024$863M39Aug 14, 202413F-HRchanges · EDGAR ↗
Q1 2024$887M38May 15, 202413F-HRchanges · EDGAR ↗
Q4 2023$1.1B34Feb 15, 2024RESTATEMENTchanges · EDGAR ↗
Q3 2023$1.1B29Nov 14, 202313F-HRchanges · EDGAR ↗
Q2 2023$1.2B30Aug 14, 202313F-HRchanges · EDGAR ↗
Q1 2023$1.2B30May 15, 202313F-HRchanges · EDGAR ↗
Q4 2022$1.2B29Feb 14, 202313F-HRchanges · EDGAR ↗
Q3 2022$1.3B32Nov 14, 202213F-HRchanges · EDGAR ↗
Q2 2022$1.1B33Aug 15, 202213F-HRchanges · EDGAR ↗
Q1 2022$1.3B35May 16, 202213F-HRchanges · EDGAR ↗
Q4 2021$1.6B37Feb 14, 202213F-HRchanges · EDGAR ↗
Q3 2021$1.7B42Nov 15, 202113F-HRchanges · EDGAR ↗
Q2 2021$1.8B42Aug 16, 202113F-HRchanges · EDGAR ↗
Q1 2021$1.8B42May 17, 202113F-HRchanges · EDGAR ↗
Q4 2020$1.9B41Feb 16, 202113F-HRchanges · EDGAR ↗
Q3 2020$1.8B43Nov 16, 202013F-HRchanges · EDGAR ↗
Q2 2020$1.7B41Aug 14, 202013F-HRchanges · EDGAR ↗
Q1 2020$1.2B37May 15, 202013F-HRchanges · EDGAR ↗
Q4 2019$1.8B37Feb 14, 202013F-HRchanges · EDGAR ↗
Q3 2019$1.5B37Nov 14, 201913F-HRchanges · EDGAR ↗
Q2 2019$2.1B39Aug 14, 201913F-HRchanges · EDGAR ↗
Q1 2019$2.4B37May 15, 201913F-HRchanges · EDGAR ↗
Q4 2018$1.9B36Feb 14, 201913F-HRchanges · EDGAR ↗

13F filings are due up to 45 days after quarter end, so holdings shown here lag the fund’s current book. Source: original SEC filing on EDGAR ↗.