Document:

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                                                                  Exhibit 4.4(c)

                       ASSIGNMENT AND ASSUMPTION AGREEMENT

          This ASSIGNMENT AND ASSUMPTION AGREEMENT, dated as of May 11, 1998
(the "Agreement"), is entered into between Telephone and Data Systems, Inc., an
Iowa corporation ("TDS Iowa") and Telephone and Data Systems, Inc., a Delaware
corporation ("TDS Delaware").

                              W I T N E S S E T H:

          WHEREAS, TDS Iowa, BankBoston N.A. (formerly known as The First
National Bank of Boston), as Agent and Arranger, LaSalle National Bank and
Toronto Dominion (Texas), Inc., as Co-Agents, and the financial institutions
named therein (individually, a "Bank" and collectively, the "Banks") are parties
to a Revolving Credit Agreement, dated as of June 7, 1996, as amended on June 2,
1997 (the "Credit Agreement"), relating to the borrowing, repaying and
reborrowing from time to time by TDS Iowa of loans up to a maximum aggregate
principal amount outstanding at any one time equal to the aggregate amount of
the Banks' commitments (the "Loans"); and

          WHEREAS, capitalized terms herein, not otherwise defined, shall have
the same meanings given them in the Credit Agreement; and

          WHEREAS, Section 6.3(b) of the Credit Agreement provides that an
agreement may be entered into by TDS Iowa, to evidence the succession of another
corporation to the capacity of Borrower under the Credit Agreement and the
assumption by such successor corporation of the covenants, conditions and
obligations of TDS Iowa; and

          WHEREAS, TDS Iowa and TDS Delaware are entering into this Agreement to
recognize the merger (the "Merger") of TDS Iowa with and into TDS Delaware, with
TDS Delaware as the surviving corporation; and

          WHEREAS, the Merger will be consummated for the sole purpose of
reincorporating TDS Iowa from Iowa to Delaware, and will not result in any
change in its name, business, management, assets or liabilities; and

          WHEREAS, all things necessary to make this Agreement a valid agreement
of TDS Iowa and TDS Delaware have been done.

          NOW, THEREFORE, in consideration of the premises and the mutual
covenants of the parties hereto, the parties hereto agree as follows:

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          Section 1. SUCCESSION OF TDS IOWA BY TDS DELAWARE

          Subject to the effectiveness of the Merger:

          (a) TDS Delaware, as successor to TDS Iowa, hereby expressly assumes
the due and punctual payment of the principal of and interest on all of the
Loans and the due and punctual performance and observance of all of the
covenants, conditions and other obligations of the Credit Agreement and the
Notes to be performed or observed by TDS Iowa as Borrower; and

          (b) TDS Delaware shall succeed to, and be substituted for, and may
exercise every right and power of, TDS Iowa under the Credit Agreement with the
same effect as if TDS Delaware had been originally named as the Borrower
therein.

          Section 2. REPRESENTATIONS AND WARRANTIES.

          TDS Iowa and TDS Delaware hereby jointly and severally represent and
warrant to the Banks and the Agent that, as of the date hereof and immediately
prior to and after giving effect to the Merger:

          (a) Representations and Warranties in Credit Agreement. The
representations and warranties of the Borrower contained in the Credit
Agreement, (i) were true and correct in all material respects when made, and
(ii) except to the extent such representations and warranties by their terms are
made solely as of a prior date or by their terms relate specifically to the
Borrower's status as an Iowa corporation, continue to be true and correct in all
material respects.

          (b) Authority, Etc. The execution and delivery by each of TDS Iowa and
TDS Delaware of this Assignment and Assumption Agreement, and the performance by
TDS Delaware, as the Borrower under the Credit Agreement after giving effect to
the Merger, of all of its agreements and obligations under the Credit Agreement
(i) are within the corporate authority of TDS Iowa and TDS Delaware,
respectively, (ii) have been duly authorized by all necessary corporate
proceedings by TDS Iowa and TDS Delaware, respectively, (iii) do not conflict
with or result in any breach or contravention of any provision of law, statute,
rule or regulation to which either TDS Iowa or TDS Delaware is subject, or any
judgment, order, writ, injunction, license or permit applicable to TDS Iowa or
TDS Delaware, and (iv) do not conflict with any provision of the corporate
charter or by-laws of, or any agreement or other instrument binding upon, TDS
Iowa or TDS Delaware.

          (c) Enforceability of Obligations. The Credit

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Agreement constitutes the legal, valid and binding obligation of TDS Iowa as of
the date hereof and immediately prior to the Merger, and of TDS Delaware
immediately after giving effect to the Merger, in each case enforceable in
accordance with its terms against TDS Iowa or TDS Delaware, in their respective
capacities as the Borrower under the Credit Agreement, subject to the
qualifications as to enforceability set forth in Section 4.1(c) of the Credit
Agreement.

          (d) Absence of Defaults. No Default or Event of Default exists under
the Credit Agreement.

          Section 3. REFERENCE TO AND EFFECT ON THE CREDIT AGREEMENT

          (a) On and after the date of this Agreement, each reference in the
Credit Agreement to "hereunder," "hereof," or "herein" shall mean and be a
reference to the Credit Agreement as supplemented by this Agreement.

          (b) The Credit Agreement shall remain in full force and effect and is
hereby ratified and confirmed.

          (c) All capitalized terms used but not otherwise defined herein shall
have the respective meanings set forth in the Credit Agreement.

          (d) This Agreement shall be effective at the time the Merger is
effective, subject to no Default or Event of Default existing under the Credit
Agreement at such time.

          Section 4. GOVERNING LAW

          This Agreement shall be governed by, and construed and enforced in
accordance with, the laws of the jurisdiction which govern the Credit Agreement
and its construction.

          Section 5. COUNTERPARTS AND METHOD OF EXECUTION

          This Agreement may be executed in several counterparts, all of which
together shall constitute one agreement binding on all parties hereto,
notwithstanding that all parties have not signed the same counterpart.

          Section 6. SECTION TITLES

          Section titles are for descriptive purposes only and shall not control
or alter the meaning of this Agreement as set forth in the text.

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          IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
be duly executed and their respective seals to be affixed hereunto and duly
attested all as of the day and year first above written.

                                   TELEPHONE AND DATA SYSTEMS, INC.,
                                   an Iowa Corporation

[Corporate Seal]
                                   By:  /s/ LEROY T. CARLSON, JR.
                                        ----------------------------------
                                        LeRoy T. Carlson, Jr.
                                        President

Attest:

/s/ MICHAEL G. HRON
-----------------------------
Michael G. Hron
Secretary

                                   TELEPHONE AND DATA SYSTEMS, INC.,
                                   a Delaware Corporation

[Corporate Seal]
                                   By:  /s/ LEROY T. CARLSON, JR.
                                        ----------------------------------
                                        LeRoy T. Carlson, Jr.
                                        President

Attest:

/s/ MICHAEL G. HRON
-----------------------------
Michael G. Hron
Secretary

Accepted and Acknowledged:

BANKBOSTON, N.A., as Agent
for the Banks referred to herein

By:  /s/ JULIE V. JALELIAN
     ------------------------
     Name:  Julie V. Jalelian
     Title: Director

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                                                                EXHIBIT 10.6(b)

                                 FIRST AMENDMENT
                                     TO THE
                        TELEPHONE AND DATA SYSTEMS, INC.
                          1998 LONG-TERM INCENTIVE PLAN

          WHEREAS, Telephone and Data Systems, Inc. (the "Corporation") has
adopted the Telephone and Data Systems, Inc. 1998 Long-Term Incentive Plan (the
"Plan") for the benefit of certain key executives and management personnel;

          WHEREAS, pursuant to Section 8.2 of the Plan, the Board may amend the
Plan as it deems advisable;

          WHEREAS, the Board desires to amend the Plan in certain respects.

          NOW, THEREFORE, BE IT RESOLVED, pursuant to the power of amendment
contained in Section 8.2 of the Plan, the Plan is hereby amended in the
following respects, effective December 1, 1999:

     1.   Section 4.1(d) of the Plan is hereby amended to read as follows:

     An option may be exercised (i) by giving written notice to the Vice
     President-Human Resources of the Company specifying the number of whole
     shares of Stock to be purchased and by accompanying such notice with
     payment therefor (in full, unless another arrangement for such payment
     which is satisfactory to the Company has been made) either (A) in cash, (B)
     in Mature Shares having a Fair Market Value, determined as of the date of
     exercise, equal to the aggregate purchase price payable by reason of such
     exercise, (C) in cash by a broker-dealer acceptable to the Company to whom
     the optionee has submitted an irrevocable notice of exercise or (D) a
     combination of (A) and (B), in each case to the extent set forth in the
     Agreement relating to the option, and (ii) by executing such documents and
     taking any other actions as the Company may reasonably request. The
     Committee shall have sole discretion to disapprove of an election pursuant
     to any of clauses (B)-(D) of the preceding sentence. If the payment of the
     purchase price is to be made pursuant to clause (B) of the first sentence
     of this Section 4.1(d), then any fraction of a share of Stock which would
     be required to pay such purchase price shall be disregarded and the
     remaining amount due shall be paid in cash by the optionee. No share of
     Stock shall be delivered until the full purchase price therefor has been
     paid.

     2.   The first sentence of Section 7.2 of the Plan is hereby amended to
delete therefrom the phrase "to be made in accordance with the Agreement
evidencing such award".

     3.   Section 8.9(b)(3) is hereby amended to delete the phrase "approval by
the shareholders of the Company of a reorganization, merger or consolidation or
sale or other disposition of all or substantially all the assets of the Company
(a "Corporate Transaction")" and

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to insert in its place the phrase "consummation of a reorganization, merger or
consolidation or sale or other disposition of all or substantially all the
assets of the Company (a "Corporate Transaction")".

          IN WITNESS WHEREOF, the undersigned has executed this amendment as of
this 10th day of March, 2000.

                                   TELEPHONE AND DATA SYSTEMS, INC.

                                   BY:  /s/ Leroy T. Carlson, Jr.
                                        -------------------------
                                        LEROY T. CARLSON, JR.
                                        PRESIDENT

             SIGNATURE PAGE TO FIRST AMENDMENT TO TELEPHONE AND DATA
                  SYSTEMS, INC. 1998 LONG-TERM INCENTIVE PLAN

                                    * * * * *

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