EMERSON ELECTRIC CO — Director's Dealing 2006

Aug 22, 2006

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2006-08-18

Reporting Person: EMERSON ELECTRIC CO (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2006-08-18	Common Stock	S	23568	$20.7929	Disposed	4394447	Indirect
2006-08-21	Common Stock	S	22994	$20.579	Disposed	4371453	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 18, 2006, as follows and as described in
Footnote 2 below: 100 shares at $20.48; 284 at $20.49; 716 at $20.50; 100 at $20.51; 800 at $20.52; 73 at $20.53; 100 at
$20.54; 100 at $20.55; 400 at $20.56; 100 at $20.57; 100 at $20.59; 300 at $20.60; 200 at $20.62; 400 at $20.63; 200 at
$20.64; 100 at $20.65; 500 at $20.66; 300 at $20.67; 400 at $20.68; 400 at $20.69; 600 at $20.70; 600 at $20.71; 400 at
$20.72; 726 at $20.73; 74 at $20.74; and 100 at $20.75.

F2: This footnote sets forth additional detail with respect to the transactions described in Footnote 1, as follows: 700 shares
at $20.76; 400 at $20.77; 26 at $20.78; 374 at $20.79; 800 at $20.80; 1,200 at $20.81; 1,026 at $20.82; 1,269 at $20.83; 590
at $20.84; 800 at $20.85; 1,006 at $20.86; 200 at $20.87; 400 at $20.88; 300 at $20.89; 300 at $20.91; 900 at $20.92; 486 at
$20.93; 414 at $20.94; 700 at $20.95; 200 at $20.97; 1,200 at $20.98; 1,104 at $20.99; and 1,000 at $21.00. The weighted
average sales price for these transactions was $20.7929 per share.

F3: The sales were effected in multiple transactions, at varying prices, on August 21, 2006, as follows: 200 shares at $20.38;
100 at $20.39; 400 at $20.40; 600 at $20.41; 500 at $20.42; 200 at $20.44; 200 at $20.45; 500 at $20.47; 274 at $20.49; 898
at $20.50; 1,002 at $20.51; 1,055 at $20.52; 545 at $20.53; 300 at $20.54; 700 at $20.55; 600 at $20.56; 600 at $20.57;
1,300 at $20.58; 1,000 at $20.59; 1,300 at $20.60; 2,100 at $20.61; 2,598 at $20.62; 1,302 at $20.63; 700 at $20.64; 600 at
$20.65; 1,100 at $20.66; 300 at $20.67; 1,033 at $20.68; 200 at $20.70; 100 at $20.71; 400 at $20.72; and 287 at $20.73. The
weighted average sales price for these transactions was $20.579 per share.