UNITED STATES
                       SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

                                  SCHEDULE 13G

                    Under the Securities Exchange Act of 1934

                                (Amendment No. 6)
                                       of
                           Tweedy, Browne Company LLC

                                (Name of Issuer)
                                Proquest Company

                         (Title of Class of Securities)
                     Common Stock, Par Value $.001 per share

                                 (Cusip Number)
                                    74346P102

                                December 31, 2006
             (Date of Event which Requires Filing of this Statement)

*    The remainder of this cover page shall be filled out for a reporting
     person's initial filing on this form with respect to the subject class of
     securities, and for any subsequent amendment containing information which
     would alter the disclosures provided in a prior cover page.

     The information required in the remainder of this cover page shall not be
deemed to be "filed" for the purpose of Section 18 of the Securities Exchange
Act of 1934("Act") or otherwise subject to the liabilities of that section of
the Act but shall be subject to all other provisions of the Act (however, see
the Notes).



CUSIP NO. 74346P102
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1.   NAME OF REPORTING PERSONS IRS IDENTIFICATION NOS OF ABOVE PERSONS
     Tweedy, Browne Company LLC ("TBC")
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2.   CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
     (a) [ ]
     (b) [ ]
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3.   SEC USE ONLY
--------------------------------------------------------------------------------
4.   CITIZENSHIP OR PLACE OF ORGANIZATION
     Delaware
--------------------------------------------------------------------------------
               5.   SOLE VOTING POWER
                    0 shares
               -----------------------------------------------------------------
  NUMBER OF    6.   SHARED VOTING POWER
   SHARES           0 shares
BENEFICIALLY   -----------------------------------------------------------------
  OWNED BY     7.   SOLE DISPOSITIVE POWER
    EACH            0 shares
  REPORTING    -----------------------------------------------------------------
   PERSON      8.   SHARED DISPOSITIVE POWER
    WITH            0 shares
               -----------------------------------------------------------------
               9.   AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
                    0 shares
--------------------------------------------------------------------------------
10.  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW(9)EXCLUDES CERTAIN SHARES* [ ]
--------------------------------------------------------------------------------
11.  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
     0%
--------------------------------------------------------------------------------
12.  TYPE OF REPORTING PERSON (See instructions)
     BD & IA
--------------------------------------------------------------------------------
13.  CHECK THE APPROPRIATE BOX TO DESIGNATE THE RULE PURSUANT TO WHICH THIS
     SCHEDULE IS FILED
     [X] Rule 13d-1(b)
     [ ] Rule 13d-1(c)
     [ ] Rule 13d-1(d)
--------------------------------------------------------------------------------



ITEM 1   (A)  NAME OF ISSUER:
              Proquest Company

ITEM 1   (B)  ADDRESS OF ISSUER'S PRINCIPAL EXECUTIVE OFFICES:
              777 Eisenhower Parkway
              Ann Arbor, Michigan 48106-1346

ITEM 2   (A)  NAME OF PERSON FILING:
              The person filing this Amendment No. 6 to a Statement on
              Schedule 13G is Tweedy, Browne Company LLC ("TBC"), a Delaware
              limited liability company.

ITEM 2   (B)  ADDRESS OF PRINCIPAL OFFICE:
              The business address of TBC is 350 Park Avenue, New York,
              NY 10022.

ITEM 2   (C)  CITIZENSHIP:
              TBC is a Delaware limited liability company.

ITEM 2   (D)  TITLE OF CLASS OF SECURITIES:
              This Amendment No. 6 relates to the Common Stock,
              par value $.001 per share of the issuer.

ITEM 2   (E)  CUSIP NUMBER:
              74346P102

ITEM 3   IF THIS STATEMENT IS FILED PURSUANT TO RULES 13D-1(B)OR 13D-2(B), CHECK
         WHETHER THE PERSON FILING IS a:

         (a)  [X] Broker or dealer registered under Section 15 of the Exchange
                  Act

         (b)  [ ] Bank as defined in Section 3(a)(6) of the Exchange Act.

         (c)  [ ] Insurance company as defined in Section 3(a)(19) of the
                  Exchange Act.

         (d)  [ ] Investment company registered under Section 8 of the
                  Investment Company Act.

         (e)  [X] An investment adviser in accordance with Rule
                  13d-1(b)(1)(ii)(E).

         (f)  [ ] An employee benefit plan or endowment fund in accordance with
                  Rule 13d-1(b)(1)(ii)(F).

         (g)  [ ] A parent holding company or control person in accordance with
                  Rule 13d-1(b)(1)(ii)(G).

         (h)  [ ] A savings association as defined in Section 3(b) of the
                  Federal Deposit Insurance Act.

         (i)  [ ] A church plan that is excluded from the definition of an
                  investment company under Section 3(c)(14) of the Investment
                  Company Act.

         (j)  [ ] Group, in accordance with Rule 13d-1(c), check this box.

ITEM 4 - OWNERSHIP

ITEM 4    (a)   Amount Beneficially Owned:
                0 shares

          (b)   Percent of Class
                0%

          (c)   Number of Shares as to which such person has:

          (i)   Sole power to vote or direct the vote:
                0 shares

         (ii)   Shared power to vote or direct the vote:
                0 shares

         (iii)  Sole power to dispose or to direct the disposition of
                0 shares

         (iv)   Shared power to dispose or to direct the disposition of
                0 shares

ITEM 5.  OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS
         [X]

ITEM 6.  OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON
         Not applicable

ITEM 7.  IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
         THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY:
         Not applicable

ITEM 8.  IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
         Not applicable

ITEM 9.  NOTICE OF DISSOLUTION OF GROUP
         Not applicable

ITEM 10. CERTIFICATION

     By signing below TBC does hereby certify that, to the best of its knowledge
and belief, the securities referred to above were acquired and disposed of in
the ordinary course of business and were not acquired and disposed of for the
purpose of and did not have the effect of changing or influencing the control of
the issuer of such securities and were not acquired and disposed of in
connection with or as a participant in any transaction having such purpose or
effect.

     TBC after reasonable inquiry and to the best of its knowledge and belief,
does hereby certify that the information set forth in the Amendment No. 6 is
true, complete and correct.

TWEEDY, BROWNE COMPANY LLC


By: /s/ Christopher H. Browne
    ---------------------------------
    Christopher H. Browne
    Managing Director

Dated: January 25, 2007