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- -------- UNITED STATES SECURITIES AND EXCHANGE COMMISSION -----------------------------
FORM 4 WASHINGTON, D.C. 20549 OMB APPROVAL
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/X/ CHECK THIS BOX IF NO STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OMB NUMBER: 3235-0287
LONGER SUBJECT TO EXPIRES: SEPTEMBER 30, 1998
SECTION 16. FORM 4 OR Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, ESTIMATED AVERAGE BURDEN
FORM 5 OBLIGATIONS MAY Section 17(a) of the Public Utility Holding Company Act of 1935 or HOURS PER RESPONSE .... 0.5
CONTINUE. SEE Section 30(f) of the Investment Company Act of 1940 -----------------------------
INSTRUCTION 1(b).
(Print or Type Responses)
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1. Name and Address of Reporting Person* 2. Issuer Name AND Ticker or Trading Symbol 6. Relationship of Reporting Person(s)
to Issuer (Check all applicable)
Director X 10% Owner
Landover Holdings Corporation Advanced Radio Telecom Corp. (ARTT) ---- ----
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(Last) (First) (Middle) 3. IRS or Social Security 4. Statement for ---- title ---- (specify
Number of Reporting Month/Year below) below
Person (Voluntary) ----------------- ------------------
156 West 56th Street - Suite 2001 5/98
- -------------------------------------------- ------------------- 7. Individual or Joint/Group Filing
(Street) 5. If Amendment, (Check Applicable Line)
Date of Original /X/ Form filed by One Reporting Person
(Month/Year) / / Form filed by More than One
New York New York 10019 Reporting Person
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(City) (State) (Zip) TABLE I - NON-DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
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1. Title of Security 2. Trans- 3. Trans- 4. Securities Acquired (A) 5. Amount of 6. Owner- 7. Nature
(Instr. 3) action action or Disposed of (D) Securities ship of In-
Date Code (Instr. 3, 4 and 5) Beneficially Form: direct
(Instr. 8) Owned at Direct Bene-
(Month/ End of (D) or ficial
Day/ ------------------------------------------- Month Indirect Owner-
Year) (A) or (I) ship
Code V Amount (D) Price (Instr. 3 (Instr. 4) (Instr. 4)
and 4)
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Common Stock 5/13/98 S 13,500 (D) 10.625 (D)
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Common Stock 5/13/98 S 6,500 (D) 10.6875 (D)
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Common Stock 6/2/98 S 2,758,864 (D) (1) (D)
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Common Stock 5/21/98 S 14,000 (D) 10 (D)
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Common Stock 5/21/98 S 7,000 (D) 10.125 (D)
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Common Stock 6/1/98 S 10,000 (D) 9.75 (D)
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Common Stock 6/1/98 S 5,000 (D) 9.875 (D)
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Common Stock 6/2/98 S 8,000 (D) 9.8125 (D)
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Common Stock 6/2/98 S 3,000 (D) 11.25 (D)
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Common Stock 6/2/98 S 2,500 (D) 12 (D)
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Common Stock 6/2/98 S 700 (D) 12.3125 (D)
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Common Stock 6/2/98 S 2,528 (D) 12.375 (D)
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0
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Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly. (Over)
* If the form is filed by more than one reporting person, SEE Instruction 4(b)(v). SEC 1474 (7-97)
POTENTIAL PERSONS WHO ARE TO RESPOND TO THE COLLECTION OF INFORMATION
CONTAINED IN THIS FORM ARE NOT REQUIRED TO RESPOND UNLESS THE FORM
DISPLAYS A CURRENTLY VALID OMB CONTROL NUMBER.
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FORM 4 (CONTINUED) TABLE II - DERIVATIVE SECURITIES ACQUIRED, DISPOSED OF, OR BENEFICIALLY OWNED
(E.G., PUTS, CALLS, WARRANTS, OPTIONS, CONVERTIBLE SECURITIES)
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1. Title of Derivative Security 2. Conver- 3. Trans- 4. Transac- 5. Number of Deriv- 6. Date Exer-
(Instr. 3) sion or action tion Code ative Securities Ac- cisable and Ex-
Exercise Date (Instr. 8) quired (A) or Dis- piration Date
Price of (Month/ posed of (D) (Month/Day/
Deriv- Day/ (Instr. 3, 4, and 5) Year)
ative Year)
Security
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Date Expira-
-------------------------------------- Exer- tion
cisable Date
Code V (A) (D)
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7. Title and Amount of Under- 8. Price 9. Number 10. Owner- 11. Nature
lying Securities of of Deriv- ship of In-
(Instr. 3 and 4) Deriv- ative Form direct
ative Securi- of De- Bene-
Secur- ties rivative ficial
ity Bene- Secu- Own-
(Instr. ficially rity: ership
5) Owned Direct (Instr. 4)
at End (D) or
Amount or of Indi-
Title Number of Month rect (I)
Shares (Instr. 4) (Instr. 4)
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Explanation of Responses:
(1) The securities were disposed of in connection with the sale of substantially all the assets and business of the Reporting
Person (including at least $1,000,000 of assets other than securities of the Issuer net of related liabilities) for aggregate
consideration consisting of 1,273,029 shares of Common Stock of WinStar Communications, Inc., having an aggregate market value on
the date of the transaction of $50,364,209.
/s/ Laurence S. Zimmerman 6/9/98
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**Intentional misstatements or omissions of facts constitute **Signature of Reporting Person Date
Federal Criminal Violations. SEE 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
Note: File three copies of this Form, one of which must be manually signed.
If space is insufficient, SEE Instruction 6 for procedure.
Potential persons who are to respond to the collection of information contained
in this form are not required to respond unless the form displays a currently
valid OMB Number.
Page 2
SEC 1474 (7-97)
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