MU gamma exposure: flip, call wall, put wall

Dealer gamma by strike for Micron Technology, from the option chain itself: two books, the level where net gamma changes sign, and the two strikes that carry the most. Expiries out to 120 days.

data as of 2026-10-12 14:59:04 ET · replay MU in the terminal
Spot
987.3
from put-call parity
Zero gamma flip
989
0.2% above spot
Call wall
1000
1.3% above spot
Put wall
985
0.2% below spot
Net gamma, volume
-$1.23B
per 1% move
Net gamma, OI
-$196M
per 1% move
Price sits below the flip at 989: on this book dealer hedging adds to a move rather than leaning against it.
The session, 2026-09-30 priceflipcall wallput wall
1100107010711068 net gamma, volume book09:3010:3011:3012:3013:3014:3015:30
day10-1210-0910-0810-0710-0610-0510-0210-0109-3009-2909-2809-25 83 points · volume book · levels drawn as they stood
Strikes through the day levelchange since the open absorbs a movefeeds itprice
1110110511001095109010851083108010781075107310701068106510631060105510501045104010351030102509:3010:3011:3012:3013:3014:3015:30
Gamma by strike, two books on one axis
OPEN INTEREST · last close
STRIKE
VOLUME · today
1060
1058
1055
1050
1045
1040
1035
1030
1025
1020
1015
1010
1005
1000
call wall
995
990
985
put wall · spot
980
975
970
965
960
955
950
945
940
935
930
925
920
915
By expiry, volume book
expiryflipcallputnet
2026-10-12 · 0DTE989.41000985-$1.51B
2026-10-14965.11025980+$122M
2026-10-169501000950+$140M
2026-10-19954.1985970+$10M
2026-10-21963.71080970+$3M
2026-10-23977.41050900+$4M
How far to trust this bookC

a single stock with an active tape; the dealer-sign convention is an approximation here.

Prints a second, regular session11.15
Strikes where the two books agree on the sign87%
Contracts traded today, expiries shown827,866

What this page assumes

  • Calls count as dealer-long gamma and puts as dealer-short. That is a convention, not a measurement: open interest does not say who holds a contract.
  • The volume book signs today's traded contracts. The open-interest book uses positions as of the last close and does not move inside the day.
  • Spot is derived from the option quotes by put-call parity, so it can sit a few cents from the last trade in the underlying.
  • MU options are American style and the underlying may pay a dividend. Each expiry is priced off its own forward from put-call parity, and gamma is Black-Scholes on that forward. Deep in-the-money contracts near a dividend are the weak spot.
  • Every figure is dollars of dealer delta per 1% move in MU, the unit that compares across symbols.
  • There is no tape-signed book on this page. That book exists only where a live engine runs.

Questions

What does it mean that MU is below its flip?

Net dealer gamma on this book is negative, so hedging flows tend to add to a move. It says nothing about direction.

Why are there two books?

Open interest is positioning as it stood at the last close. Volume is what traded today. When they disagree, that split is the reading.

Is this a trading signal?

No. We tested wall touches and flip crosses on SPX across more than a thousand sessions and found no edge that survives costs. These are measurements of where hedging concentrates.

How is this different from the SPX terminal?

SPX runs on a live engine: every second, with a third book signed print by print from the trade tape. This page is rebuilt from chain snapshots and carries the two conventional books only.