EMERSON ELECTRIC CO — Director's Dealing 2006

Aug 30, 2006

SEC Form 4 — Statement of Changes in Beneficial Ownership

Issuer: MKS INSTRUMENTS INC (MKSI)
CIK: 0001049502
Period of Report: 2006-08-28

Reporting Person: EMERSON ELECTRIC CO (10% Owner)

Non-Derivative Transactions

Date	Security	Code	Shares	Price	A/D	Holdings After	Ownership
2006-08-28	Common Stock	S	51000	$20.5584	Disposed	4066399	Indirect
2006-08-29	Common Stock	S	50000	$20.3815	Disposed	4016399	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 28, 2006, as follows and as described in
Footnote 2 below: 100 shares at $20.13; 300 at $20.14; 100 at $20.15; 200 at $20.17; 153 at $20.19; 100 at $20.21; 100 at
$20.26; 300 at $20.31; 620 at $20.35; 580 at $20.36; 100 at $20.37; 200 at $20.38; 600 at $20.39; 100 at $20.40; 300 at
$20.41; 100 at $20.43; 100 at $20.44; and 400 at $20.45.

F2: This footnote sets forth additional detail with respect to the transactions described in Footnote 1, as follows: 300 shares
at $20.46; 400 at $20.47; 1,400 at $20.48; 400 at $20.49; 2,600 at $20.50; 2,266 at $20.51; 781 at $20.52; 900 at $20.53;
800 at $20.54; 1,900 at $20.55; 2,000 at $20.56; 1,900 at $20.57; 400 at $20.58; 3,600 at $20.59; 11,700 at $20.60; 1,100 at
$20.61; and 14,100 at $20.62. The weighted average sales price for these transactions was $20.5584 per share.

F3: The sales were effected in multiple transactions, at varying prices, on August 29, 2006, as follows and as described in
Footnote 4 below: 500 shares at $20.15; 700 at $20.16; 200 at $20.17; 200 at $20.18; 200 at $20.19; 200 at $20.20; 446 at
$20.21; 957 at $20.22; 642 at $20.23; 1,297 at $20.24; 1,158 at $20.25; 600 at $20.26; 1,782 at $20.27; 1,010 at $20.28;
1,890 at $20.29; 2,000 at $20.30; 1,742 at $20.31; 458 at $20.32; 700 at $20.33; 600 at $20.34; 500 at $20.35; 700 at
$20.36; and 400 at $20.37.

F4: This footnote sets forth additional detail with respect to the transactions described in Footnote 3, as follows: 400 shares
at $20.38; 800 at $20.39; 870 at $20.40; 1,830 at $20.41; 4,600 at $20.42; 3,723 at $20.43; 7,400 at $20.44; 1,833 at
$20.45; 1,933 at $20.46; 1,167 at $20.47; 1,658 at $20.48; 1,150 at $20.49; 2,132 at $20.50; 416 at $20.51; 102 at $20.53;
204 at $20.54; 15 at $20.55; 685 at $20.56; and 200 at $20.57. The weighted average sales price for these transactions was
$20.3815 per share.