WST · West Pharmaceutical Services Inc

Track WST — free Ask ALVIS about WST

$340.96 +1.37 (+0.40%) At close · Jul 31

Market Cap

$24.00B

70.38M

Options Chain

15-min delayed Underlying $340.96 · at close Jul 31, 2026 Options Calculator

Positioning

Aug 21, 2026 · 20 days to expiry · 58 contracts

Put / call OI

0.59

Call-heavy positioning

Open interest

1,261

contracts outstanding

Volume

433

traded today

Max pain

$350.00

$9.04 above spot

ATM implied vol

29.7%

market's expected move

Open interest by strike · near the money

Calls Puts

195

200

210

220

230

240

250

260

270

280

290

300

310

320

330

340

350

360

370

380

390

400

410

420

430

440

450

460

470

Chain

Click any strike for greeks, breakeven and the calculator

Expiry

Aug 21 20d Sep 18 48d Dec 18 139d Jan 15 167d Mar 19 230d Dec 17 503d

Calls						Puts
OI	Vol	IV	Δ	Last	Strike	Last	Δ	IV	Vol	OI
2	2	107.6%	0.992	$179.00		—	-0.021	129.4%	—	0
Call · $195 In the money Last $179.00 Breakeven $374.00 Implied vol 107.6% Delta 0.992 ≈99% ITM Gamma 0 Theta -0.064 Vega 0.013 Open interest 2 Model this call Put · $195 Last — Breakeven — Implied vol 129.4% Delta -0.021 ≈2% ITM Gamma 0 Theta -0.131 Vega 0.03 Open interest 0 Model this put
2	2	91.1%	0.996	$174.00		—	-0.02	121.2%	—	0
Call · $200 In the money Last $174.00 Breakeven $374.00 Implied vol 91.1% Delta 0.996 ≈100% ITM Gamma 0 Theta -0.038 Vega 0.013 Open interest 2 Model this call Put · $200 Last — Breakeven — Implied vol 121.2% Delta -0.02 ≈2% ITM Gamma 0.001 Theta -0.117 Vega 0.031 Open interest 0 Model this put
1	1	95.2%	0.99	$164.00		—	-0.01	96%	—	0
Call · $210 In the money Last $164.00 Breakeven $374.00 Implied vol 95.2% Delta 0.99 ≈99% ITM Gamma 0 Theta -0.067 Vega 0.031 Open interest 1 Model this call Put · $210 Last — Breakeven — Implied vol 96% Delta -0.01 ≈1% ITM Gamma 0 Theta -0.052 Vega 0.031 Open interest 0 Model this put
0	—	76.6%	0.995	—		—	-0.025	103.7%	—	0
Call · $220 In the money Last — Breakeven — Implied vol 76.6% Delta 0.995 ≈99% ITM Gamma 0 Theta -0.041 Vega 0.014 Open interest 0 Model this call Put · $220 Last — Breakeven — Implied vol 103.7% Delta -0.025 ≈3% ITM Gamma 0.001 Theta -0.121 Vega 0.064 Open interest 0 Model this put
0	—	71.6%	0.993	—		$0.25	-0.054	116.1%	1	1
Call · $230 In the money Last — Breakeven — Implied vol 71.6% Delta 0.993 ≈99% ITM Gamma 0 Theta -0.047 Vega 0.014 Open interest 0 Model this call Put · $230 Last $0.25 Breakeven $229.75 Implied vol 116.1% Delta -0.054 ≈5% ITM Gamma 0.001 Theta -0.255 Vega 0.114 Open interest 1 Model this put
0	—	63.3%	0.993	—		$1.12	-0.051	100.2%	1	1
Call · $240 In the money Last — Breakeven — Implied vol 63.3% Delta 0.993 ≈99% ITM Gamma 0 Theta -0.044 Vega 0.014 Open interest 0 Model this call Put · $240 Last $1.12 Breakeven $238.88 Implied vol 100.2% Delta -0.051 ≈5% ITM Gamma 0.001 Theta -0.209 Vega 0.067 Open interest 1 Model this put
0	—	58.8%	0.991	—		—	-0.06	92.8%	—	0
Call · $250 In the money Last — Breakeven — Implied vol 58.8% Delta 0.991 ≈99% ITM Gamma 0.001 Theta -0.05 Vega 0.015 Open interest 0 Model this call Put · $250 Last — Breakeven — Implied vol 92.8% Delta -0.06 ≈6% ITM Gamma 0.002 Theta -0.219 Vega 0.119 Open interest 0 Model this put
0	—	53.5%	0.989	—		$0.95	-0.061	81.1%	1	5
Call · $260 In the money Last — Breakeven — Implied vol 53.5% Delta 0.989 ≈99% ITM Gamma 0.001 Theta -0.054 Vega 0.035 Open interest 0 Model this call Put · $260 Last $0.95 Breakeven $259.05 Implied vol 81.1% Delta -0.061 ≈6% ITM Gamma 0.002 Theta -0.195 Vega 0.121 Open interest 5 Model this put
0	—	47.5%	0.985	—		$1.35	-0.07	72.5%	20	4
Call · $270 In the money Last — Breakeven — Implied vol 47.5% Delta 0.985 ≈99% ITM Gamma 0.001 Theta -0.058 Vega 0.035 Open interest 0 Model this call Put · $270 Last $1.35 Breakeven $268.65 Implied vol 72.5% Delta -0.07 ≈7% ITM Gamma 0.002 Theta -0.193 Vega 0.123 Open interest 4 Model this put
1	2	41.8%	0.982	$80.10		$0.26	-0.044	51.7%	1	3
Call · $280 In the money Last $80.10 Breakeven $360.10 Implied vol 41.8% Delta 0.982 ≈98% ITM Gamma 0.001 Theta -0.062 Vega 0.036 Open interest 1 Model this call Put · $280 Last $0.26 Breakeven $279.74 Implied vol 51.7% Delta -0.044 ≈4% ITM Gamma 0.002 Theta -0.095 Vega 0.072 Open interest 3 Model this put
1	2	41.8%	0.957	$71.00		$0.82	-0.055	45.7%	36	10
Call · $290 In the money Last $71.00 Breakeven $361.00 Implied vol 41.8% Delta 0.957 ≈96% ITM Gamma 0.003 Theta -0.1 Vega 0.073 Open interest 1 Model this call Put · $290 Last $0.82 Breakeven $289.18 Implied vol 45.7% Delta -0.055 ≈6% ITM Gamma 0.003 Theta -0.101 Vega 0.073 Open interest 10 Model this put
1	1	35.9%	0.945	$62.20		$0.75	-0.074	39.6%	74	214
Call · $300 In the money Last $62.20 Breakeven $362.20 Implied vol 35.9% Delta 0.945 ≈95% ITM Gamma 0.004 Theta -0.105 Vega 0.074 Open interest 1 Model this call Put · $300 Last $0.75 Breakeven $299.25 Implied vol 39.6% Delta -0.074 ≈7% ITM Gamma 0.004 Theta -0.108 Vega 0.129 Open interest 214 Model this put
1	6	36%	0.885	$26.30		$1.45	-0.105	34.1%	47	33
Call · $310 In the money Last $26.30 Breakeven $336.30 Implied vol 36% Delta 0.885 ≈89% ITM Gamma 0.007 Theta -0.165 Vega 0.131 Open interest 1 Model this call Put · $310 Last $1.45 Breakeven $308.55 Implied vol 34.1% Delta -0.105 ≈10% ITM Gamma 0.007 Theta -0.121 Vega 0.131 Open interest 33 Model this put
0	—	35.2%	0.799	—		$4.28	-0.177	31.1%	8	23
Call · $320 In the money Last — Breakeven — Implied vol 35.2% Delta 0.799 ≈80% ITM Gamma 0.01 Theta -0.223 Vega 0.202 Open interest 0 Model this call Put · $320 Last $4.28 Breakeven $315.72 Implied vol 31.1% Delta -0.177 ≈18% ITM Gamma 0.011 Theta -0.157 Vega 0.201 Open interest 23 Model this put
12	6	32.3%	0.689	$17.00		$6.20	-0.298	29.5%	1	5
Call · $330 In the money Last $17.00 Breakeven $347.00 Implied vol 32.3% Delta 0.689 ≈69% ITM Gamma 0.014 Theta -0.25 Vega 0.269 Open interest 12 Model this call Put · $330 Last $6.20 Breakeven $323.80 Implied vol 29.5% Delta -0.298 ≈30% ITM Gamma 0.015 Theta -0.197 Vega 0.269 Open interest 5 Model this put
29	2	31.2%	0.54	$10.44		$11.74	-0.462	28.2%	1	24
Call · $340 In the money Last $10.44 Breakeven $350.44 Implied vol 31.2% Delta 0.54 ≈54% ITM Gamma 0.016 Theta -0.267 Vega 0.316 Open interest 29 Model this call Put · $340 Last $11.74 Breakeven $328.26 Implied vol 28.2% Delta -0.462 ≈46% ITM Gamma 0.018 Theta -0.214 Vega 0.316 Open interest 24 Model this put
Underlying $340.96
59	19	30.7%	0.379	$5.10		$25.30	-0.641	27.6%	1	52
Call · $350 Last $5.10 Breakeven $355.10 Implied vol 30.7% Delta 0.379 ≈38% ITM Gamma 0.016 Theta -0.249 Vega 0.323 Open interest 59 Model this call Put · $350 In the money Last $25.30 Breakeven $324.70 Implied vol 27.6% Delta -0.641 ≈64% ITM Gamma 0.018 Theta -0.191 Vega 0.283 Open interest 52 Model this put
291	9	27.7%	0.219	$2.60		$20.58	-0.787	27.9%	1	55
Call · $360 Last $2.60 Breakeven $362.60 Implied vol 27.7% Delta 0.219 ≈22% ITM Gamma 0.013 Theta -0.171 Vega 0.223 Open interest 291 Model this call Put · $360 In the money Last $20.58 Breakeven $339.42 Implied vol 27.9% Delta -0.787 ≈79% ITM Gamma 0.014 Theta -0.144 Vega 0.22 Open interest 55 Model this put
76	4	29.9%	0.133	$0.90		$18.98	-0.913	26%	40	32
Call · $370 Last $0.90 Breakeven $370.90 Implied vol 29.9% Delta 0.133 ≈13% ITM Gamma 0.009 Theta -0.134 Vega 0.152 Open interest 76 Model this call Put · $370 In the money Last $18.98 Breakeven $351.02 Implied vol 26% Delta -0.913 ≈91% ITM Gamma 0.009 Theta -0.065 Vega 0.136 Open interest 32 Model this put
37	24	31.1%	0.074	$0.55		$31.80	-0.957	28.4%	5	5
Call · $380 Last $0.55 Breakeven $380.55 Implied vol 31.1% Delta 0.074 ≈7% ITM Gamma 0.006 Theta -0.09 Vega 0.09 Open interest 37 Model this call Put · $380 In the money Last $31.80 Breakeven $348.20 Implied vol 28.4% Delta -0.957 ≈96% ITM Gamma 0.006 Theta -0.038 Vega 0.069 Open interest 5 Model this put
13	1	36.3%	0.064	$1.60		$38.90	-0.963	33.7%	2	0
Call · $390 Last $1.60 Breakeven $391.60 Implied vol 36.3% Delta 0.064 ≈6% ITM Gamma 0.004 Theta -0.093 Vega 0.09 Open interest 13 Model this call Put · $390 In the money Last $38.90 Breakeven $351.10 Implied vol 33.7% Delta -0.963 ≈96% ITM Gamma 0.004 Theta -0.041 Vega 0.069 Open interest 0 Model this put
133	1	54%	0.118	$0.50		—	—	—	—	0
Call · $400 Last $0.50 Breakeven $400.50 Implied vol 54% Delta 0.118 ≈12% ITM Gamma 0.005 Theta -0.217 Vega 0.155 Open interest 133 Model this call Put · $400 In the money Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this put
41	67	52.5%	0.075	$1.05		—	-0.971	43.9%	—	0
Call · $410 Last $1.05 Breakeven $411.05 Implied vol 52.5% Delta 0.075 ≈7% ITM Gamma 0.003 Theta -0.151 Vega 0.091 Open interest 41 Model this call Put · $410 In the money Last — Breakeven — Implied vol 43.9% Delta -0.971 ≈97% ITM Gamma 0.003 Theta -0.046 Vega 0.067 Open interest 0 Model this put
10	1	51.7%	0.049	$1.08		—	—	—	—	0
Call · $420 Last $1.08 Breakeven $421.08 Implied vol 51.7% Delta 0.049 ≈5% ITM Gamma 0.002 Theta -0.105 Vega 0.093 Open interest 10 Model this call Put · $420 In the money Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this put
20	2	56.4%	0.046	$0.65		—	—	—	—	0
Call · $430 Last $0.65 Breakeven $430.65 Implied vol 56.4% Delta 0.046 ≈5% ITM Gamma 0.002 Theta -0.109 Vega 0.094 Open interest 20 Model this call Put · $430 In the money Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this put
49	1	67.7%	0.064	$1.55		—	—	—	—	0
Call · $440 Last $1.55 Breakeven $441.55 Implied vol 67.7% Delta 0.064 ≈6% ITM Gamma 0.002 Theta -0.171 Vega 0.094 Open interest 49 Model this call Put · $440 In the money Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this put
8	10	67.4%	0.046	$1.00		$100.50	-0.978	61.1%	2	0
Call · $450 Last $1.00 Breakeven $451.00 Implied vol 67.4% Delta 0.046 ≈5% ITM Gamma 0.002 Theta -0.132 Vega 0.096 Open interest 8 Model this call Put · $450 In the money Last $100.50 Breakeven $349.50 Implied vol 61.1% Delta -0.978 ≈98% ITM Gamma 0.002 Theta -0.051 Vega 0.038 Open interest 0 Model this put
5	22	87.2%	0.084	$0.85		—	-0.979	65%	—	0
Call · $460 Last $0.85 Breakeven $460.85 Implied vol 87.2% Delta 0.084 ≈8% ITM Gamma 0.002 Theta -0.274 Vega 0.096 Open interest 5 Model this call Put · $460 In the money Last — Breakeven — Implied vol 65% Delta -0.979 ≈98% ITM Gamma 0.001 Theta -0.052 Vega 0.038 Open interest 0 Model this put
2	6	90.9%	0.079	$1.05		—	—	—	—	0
Call · $470 Last $1.05 Breakeven $471.05 Implied vol 90.9% Delta 0.079 ≈8% ITM Gamma 0.002 Theta -0.272 Vega 0.097 Open interest 2 Model this call Put · $470 In the money Last — Breakeven — Implied vol — Delta — Gamma — Theta — Vega — Open interest 0 Model this put

About this data

Greeks, implied volatility, open interest and the last price come from the latest daily snapshot and are 15-minute delayed. Bid and ask are not included on this plan.

In-the-money strikes are tinted, deepening toward the money, and the bar beside each open-interest figure scales to the heaviest strike shown. The 25 strikes around the money are shown by default — switch to "All 29" for the wings. Max pain is the listed strike where the most open interest would expire worthless — a positioning reference, not a forecast.

Key facts CIK 105770 CUSIP 955306105 13F (30d) 333 filings 306 filers Visit website