Ticker · CUSIP 58502B106

MD

MEDNAX INC

Healthcare·Medical Care Facilities

···Share

Holders (tracked)

Combined shares

4,042,112

Combined value

$86.46M

Last close

$23.07

Quarter

2025Q4

Price is +7.9% vs the avg quarter-end implied price across tracked holders.

Price · 1Y$23.07+10.25 (+79.95%)H $24.65 · L $11.98 · Avg Vol 850K

Tracked holders · last 8 quarters

-2 vs previous quarter over the last 8.

SEC event timeline

16 events

AQR Capital Management added2026-02-17
+24,633 shares · 2025Q4
Position
Izzy Englander (Millennium Mgmt) trimmed2026-02-17
−88,032 shares · 2025Q4
Position
Ken Griffin (Citadel Advisors) trimmed2026-02-17
−14,392 shares · 2025Q4
Position
Steve Cohen (Point72) exited2026-02-17
−67,769 shares · 2025Q4
Position
D.E. Shaw & Co. trimmed2026-02-17
−169,118 shares · 2025Q4
Position
T. Rowe Price added2026-02-17
+3,790 shares · 2025Q4
Position
Renaissance Technologies added2026-02-12
+51,700 shares · 2025Q4
Position
Paul Tudor Jones (Tudor Investment) exited2025-12-09
−281,113 shares · 2025Q3
Position
AQR Capital Management added2025-11-14
+132,263 shares · 2025Q3
Position
Izzy Englander (Millennium Mgmt) trimmed2025-11-14
−165,695 shares · 2025Q3
Position
Steve Cohen (Point72) trimmed2025-11-14
−483,074 shares · 2025Q3
Position
Two Sigma Investments opened position2025-11-14
+39,672 shares · 2025Q3
Position
D.E. Shaw & Co. added2025-11-14
+443,575 shares · 2025Q3
Position
T. Rowe Price trimmed2025-11-14
−2,795 shares · 2025Q3
Position
Renaissance Technologies added2025-11-13
+102,100 shares · 2025Q3
Position
Norges Bank (Norway SWF) trimmed2025-11-12
−507,619 shares · 2024Q3
Position

Insider activity

No insider transactions in the last 30 days.

View full insider history for MD →

Follow-the-investor returns

If you'd copied each holder of MD…

Cost basis inferred from each manager's quarter-over-quarter position changes. Sorted by % return on the position they're still holding.

Investor	First in	Cost basis	Return	Position value today
Two Sigma Investments	2017Q3	$12.54	+84.0%	$915K
Renaissance Technologies	2016Q1	$13.62	+69.4%	$31.3M
Izzy Englander (Millennium Mgmt)	2017Q2	$13.74	+67.9%	$1.8M
AQR Capital Management	2016Q1	$13.89	+66.1%	$12.7M
Ken Griffin (Citadel Advisors)	2016Q1	$16.39	+40.8%	$1.8M
D.E. Shaw & Co.	2017Q3	$17.72	+30.2%	$42.7M
T. Rowe Price	2016Q1	$28.33	-18.6%	$2.0M

Who moved on this name in 2025Q4

Position changes reported for the latest quarter, grouped by direction.

New positions0

—

Added to3

Renaissance Technologies
+51,700
$1.1M
AQR Capital Management
+24,633
$527K
T. Rowe Price
+3,790
$81

Trimmed3

D.E. Shaw & Co.
−169,118
$3.6M
Izzy Englander (Millennium Mgmt)
−88,032
$1.9M
Ken Griffin (Citadel Advisors)
−14,392
$308K

Exited1

Steve Cohen (Point72)
−67,769
$1.1M

Institutional ownership over time

Distinct super-investors holding this ticker · combined dollar value, by quarter.

Quarter	Holders	Shares	Combined value	Δ holders
2022Q1	11	17,328,199	$17.01B	—
2022Q2	9	16,182,894	$15.52B	-2
2022Q3	11	16,212,425	$267.7M	+2
2022Q4	11	16,373,649	$243.3M	—
2023Q1	15	17,636,657	$262.9M	+4
2023Q2	14	17,892,880	$254.3M	-1
2023Q3	13	17,472,118	$222.1M	-1
2023Q4	11	17,974,907	$167.2M	-2
2024Q1	12	16,898,765	$169.5M	+1
2024Q2	13	19,582,072	$147.6M	+1
2024Q3	11	4,920,324	$56.8M	-2
2024Q4	9	4,172,705	$54.7M	-2
2025Q1	10	4,092,702	$59.1M	+1
2025Q2	9	5,107,403	$73.2M	-1
2025Q3	9	4,315,300	$72.1M	—
2025Q4	7	4,042,112	$86.5M	-2

Who owns MD

7 super-investors · 2025Q4

Tracked stake

4.04M

Combined value

$86M

% of shares outstanding

—

shares-out unknown

Quarter action mix

Added3Trim3Held1

#	Manager	Shares	Value	% of book	Last action
1	D.E. Shaw & Co.	1.85M	$40M	0.0%	Trim−169.1K
2	Renaissance Technologies	1.36M	$29M	0.0%	Added+51.7K
3	AQR Capital Management	551.8K	$12M	0.0%	Added+24.6K
4	T. Rowe Price	86.6K	$2M	0.0%	Added+3.8K
5	Ken Griffin Citadel Advisors	78.1K	$2M	0.0%	Trim−14.4K
6	Izzy Englander Millennium Mgmt	76.1K	$2M	0.0%	Trim−88.0K
7	Two Sigma Investments	39.7K	$849K	0.0%	Held

Recent moves

20 transactions

ADDAQR Capital Management
+24,633 · 2025Q4
TRIMD.E. Shaw & Co.
−169,118 · 2025Q4
TRIMKen Griffin (Citadel Advisors)
−14,392 · 2025Q4
TRIMIzzy Englander (Millennium Mgmt)
−88,032 · 2025Q4
SOLDSteve Cohen (Point72)
−67,769 · 2025Q4
ADDT. Rowe Price
+3,790 · 2025Q4
ADDRenaissance Technologies
+51,700 · 2025Q4
SOLDPaul Tudor Jones (Tudor Investment)
−281,113 · 2025Q3
ADDD.E. Shaw & Co.
+443,575 · 2025Q3
TRIMT. Rowe Price
−2,795 · 2025Q3
TRIMSteve Cohen (Point72)
−483,074 · 2025Q3
TRIMIzzy Englander (Millennium Mgmt)
−165,695 · 2025Q3
ADDAQR Capital Management
+132,263 · 2025Q3
NEWTwo Sigma Investments
+39,672 · 2025Q3
ADDRenaissance Technologies
+102,100 · 2025Q3
TRIMNorges Bank (Norway SWF)
−507,619 · 2024Q3
ADDT. Rowe Price
+4,992 · 2025Q2
NEWSteve Cohen (Point72)
+550,843 · 2025Q2
ADDIzzy Englander (Millennium Mgmt)
+248,049 · 2025Q2
SOLDTwo Sigma Investments
−31,328 · 2025Q2

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