Check the appropriate box to designate the rule pursuant to which this Schedule is filed:

2

Item 1.

(a)

Name of Issuer

         Entegris, Inc.

(b)

Address of Issuer's Principal Executive Offices

3500 Lyman Boulevard
Chaska, Minnesota 55318

Item 2.

(a)

Name of Person Filing

Cooke & Bieler, L.P.

(b)

Address of Principal Business Office or, if none, Residence

1700 Market Street
Philadelphia, PA 19103

(c)

Citizenship

Pennsylvania

(d)

Title of Class of Securities

Common Stock

(e)

CUSIP Number

29362U10

Item 3.

If this statement is filed pursuant to §§240.13d-1(b) or 240.13d-2(b) or (c), check whether the person filing is a:

(a)

[    ]

Broker or dealer registered under section 15 of the Act (15 U.S.C. 78o).

(b)

[    ]

Bank as defined in section 3(a)(6) of the Act (15 U.S.C. 78c).

(c)

[    ]

Insurance company as defined in section 3(a)(19) of the Act (15 U.S.C. 78c).

(d)

[    ]

Investment company registered under section 8 of the Investment Company Act of 1940 (15 U.S.C 80a-8).

(e)

[ X ]

An investment adviser in accordance with §240.13d-1(b)(1)(ii)(E);

(f)

[    ]

An employee benefit plan or endowment fund in accordance with §240.13d-1(b)(1)(ii)(F);

(g)

[    ]

A parent holding company or control person in accordance with § 240.13d-1(b)(1)(ii)(G);

(h)

[    ]

A savings associations as defined in Section 3(b) of the Federal Deposit Insurance Act (12 U.S.C. 1813);

(i)

[    ]

A church plan that is excluded from the definition of an investment company under section 3(c)(14) of the Investment Company Act of 1940 (15 U.S.C. 80a-3);

(j)

[    ]

Group, in accordance with §240.13d-1(b)(1)(ii)(J).

Item 4.

Ownership.

(a)

Amount beneficially owned:

         9,095,950

(b)

Percent of class:

         6.7%

(c)

Number of shares as to which the person has:

(i)

Sole power to vote or to direct the vote

         0

(ii)

Shared power to vote or to direct the vote

         4,451,600

(iii)

Sole power to dispose or to direct the disposition of

         0

(iv)

Shared power to dispose or to direct the disposition of

         9,046,850

Item 5.

Ownership of Five Percent or Less of a Class

          If this statement is being filed to report the fact that as of the date hereof the reporting person has ceased to be the beneficial owner of more than five percent of the class of securities, check the following [    ].

Instruction: Dissolution of a group requires a response to this item.

         

Item 6.

Ownership of More than Five Percent on Behalf of Another Person

Item 7.

Identification and Classification of the Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person

Item 8.

Identification and Classification of Members of the Group

Item 9.

Notice of Dissolution of Group

Item 10.

Certifications

                   By signing below I certify that, to the best of my knowledge and belief, the securities referred to above were acquired and are held in the ordinary course of business and were not acquired and are not held for the purpose of or with the effect of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with or as a participant in any transaction having that purpose or effect.

        After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

3