EMERSON ELECTRIC CO — Director's Dealing 2006

Aug 8, 2006

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2006-08-04

Reporting Person: EMERSON ELECTRIC CO (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2006-08-04	Common Stock	S	46008	$20.1398	Disposed	4873543	Indirect
2006-08-07	Common Stock	S	28600	$19.7952	Disposed	4844943	Indirect

Holdings (Non-Derivative)

Security	Shares	Ownership
Common Stock	1065182	Direct

Footnotes

F1: The sales were effected in multiple transactions, at varying prices, on August 4, 2006, as follows and as described in
Footnote 2 below: 200 shares at $19.78; 800 at $19.79; 1,300 at $19.80; 1,300 at $19.81; 300 at $19.82; 900 at $19.83;
1,100 at $19.84; 300 at $19.85; 500 at $19.86; 400 at $19.87; 300 at $19.88; 600 at $19.89; 524 at $19.90; 1,676 at $19.91;
2,200 at $19.92; 1,400 at $19.93; 1,608 at $19.94; 1,400 at $19.95; 1,500 at $19.96; 300 at $19.97; 500 at $19.98; 1,200 at
$19.99; 1,700 at $20.00; 700 at $20.01; 200 at $20.02; 700 at $20.03; 400 at $20.04; 900 at $20.05; 1,800 at $20.06; 100 at
$20.08; 300 at $20.09; 200 at $20.10; 200 at $20.11; 200 at $20.12; 100 at $20.13; 100 at $20.15; 200 at $20.16; and 400 at
$20.17.

F2: This footnote sets forth additional detail with respect to the transactions described in Footnote 1, as follows: 200 shares
at $20.18; 200 at $20.19; 200 at $20.22; 200 at $20.23; 500 at $20.24; 100 at $20.25; 543 at $20.26; 257 at $20.27; 300 at
$20.28; 200 at $20.29; 300 at $20.30; 100 at $20.33; 200 at $20.34; 700 at $20.35; 400 at $20.36; 200 at $20.39; 300 at
$20.40; 100 at $20.41; 400 at $20.42; 500 at $20.43; 400 at $20.44; 300 at $20.45; 400 at $20.46; 500 at $20.47; 2,000 at
$20.48; 500 at $20.49; 1,300 at $20.50; 400 at $20.51; 300 at $20.52; 100 at $20.53; 600 at $20.54; 100 at $20.56; 300 at
$20.57; 956 at $20.58; 344 at $20.59; 1,100 at $20.60; 500 at $20.61; 200 at $20.62; 800 at $20.63; 100 at $20.64; 100 at
$20.65; 100 at $20.69; and 200 at $20.74. The weighted average sales price for these transactions was $20.1398 per share.

F3: The sales were effected in multiple transactions, at varying prices, on August 7, 2006, as follows and as described in
Footnote 4 below: 200 shares at $19.64; 300 at $19.65; 200 at $19.66; 600 at $19.67; 600 at $19.68; 1,200 at $19.69; 1,200
at $19.70; 870 at $19.71; 700 at $19.72; 1,330 at $19.73; 2,700 at $19.74; 1,000 at $19.75; 900 at $19.76; 1,000 at $19.77;
2,900 at $19.78; 1,700 at $19.79; 1,000 at $19.80; 1,600 at $19.81; 1,000 at $19.82; 600 at $19.83; 1,000 at $19.84; and 500
at $19.85.

F4: This footnote sets forth additional detail with respect to the transactions described in Footnote 3, as follows: 700 shares
at $19.86; 1,100 at $19.87; 100 at $19.88; 500 at $19.89; 100 at $19.90; 200 at $19.91; 200 at $19.94; 100 at $19.96; 200 at
$19.98; 400 at $19.99; 200 at $20.01; 303 at $20.02; 500 at $20.03; 297 at $20.06; 500 at $20.08; and 100 at $20.09. The
weighted average sales price for these transactions was $19.7952 per share.