SECURITIES AND EXCHANGE COMMISSION
                             WASHINGTON, D.C. 20549

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                                    FORM 8-K

                                 CURRENT REPORT
                     PURSUANT TO SECTION 13 OR 15(D) OF THE
                         SECURITIES EXCHANGE ACT OF 1934


         Date of Report (Date of earliest event reported): June 12, 2002


                    CELLULAR TECHNICAL SERVICES COMPANY, INC.
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               (Exact Name of Registrant as Specified in Charter)


       Delaware                          0-19437                11-2962080
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(State or Other Jurisdiction          (Commission              (IRS Employer
     of Incorporation)                  File No.)            Identification No.)


2815 Second Avenue, Suite 100, Seattle, Washington                      98121
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(Address of Principal Executive Offices)                              (Zip Code)


       Registrant's telephone number, including area code: (206) 443-6400


                                 Not Applicable
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          (Former Name or Former Address, if Changed Since Last Report)

ITEM 5. OTHER EVENTS On June 14, 2002, trading of Cellular Technical Services Company, Inc. (the "Company"), common stock will move from the Nasdaq National Market to the Nasdaq Small Cap Market. The Company's common stock will continue trading under its current symbol (CTSC). The Company issued a press release regarding the above on June 12, 2002 that is filed herewith as an exhibit. ITEM 7. FINANCIAL STATEMENTS, PRO FORMA FINANCIAL INFORMATION AND EXHIBITS. (a) Exhibits -------- 99.1 Press Release dated June 12, 2002 2

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, as amended, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized. Dated: June 13, 2002 Cellular Technical Services Company, Inc. By: /s/ Bruce R. York -------------------------------------- Name: Bruce R. York Title: Vice President and Chief Financial Officer 3

EXHIBIT INDEX ------------- Exhibit No. Description - ----------- ----------- 99.1 Press Release dated June 12, 2002 1

                                                                    Exhibit 99.1


FOR IMMEDIATE RELEASE       Company Contact:    Bruce R. York
                                                Vice President and CFO
                                                (206) 733-8180

      CELLULAR TECHNICAL SERVICES ANNOUNCES MOVE TO NASDAQ SMALL CAP MARKET

Seattle, June 12, 2002 - Cellular Technical Services Company, Inc. (Nasdaq NM
Symbol: CTSC) ("CTS"), a provider of products and services for the prepaid and
wireless communications industries, announced today that trading of its common
shares will be moved from the Nasdaq National Market to the Nasdaq Small Cap
Market effective at the opening of business on June 14, 2002. The change is
being made as the market value of CTS' public float (i.e. shares held by
non-affiliates) has fallen below the minimum level required in order to remain
on the Nasdaq National Market. CTS elected to apply for listing on the Nasdaq
Small Cap Market to ensure the continuity of its Nasdaq listing. CTS' common
stock will continue trading under its current symbol (CTSC). Daily trading
volume and closing price will continue to be available on the same basis as
previously available from online services, financial newspapers and general
circulation newspapers.

Over the past 13 years, CTS has used its experience with real-time wireless call
processing to create technologically advanced solutions for the wireless
industry, including integrated solutions for fraud management. Today, CTS is
building a more diversified organization focusing on two areas: (i) distributing
a wide range of prepaid telecommunications products and (ii) developing and
marketing a software platform and applications for the emerging wireless
location-based services marketplace.

SPECIAL NOTE REGARDING FORWARD-LOOKING STATEMENTS: This press release may
contain forward-looking statements within the meaning of the Private Securities
Litigation Reform Act of 1995 that involve risks and uncertainties that could
cause actual results for CTS or its affiliates to differ materially from those
expressed or implied in the applicable statements. These risks and uncertainties
include but are not limited to: vulnerability to rapid industry change and
technological obsolescence; limited customer base and reliance on a relatively
small number of customers and customer contracts; dependence on a limited number
of existing products and services; uncertainty of continued demand for and
market penetration of its existing products and services under existing and
future contracts; uncertainty in its ability to timely develop, introduce and
gain acceptance of new products and services; uncertainty of the demand for and
market penetration of new products and services; the possible impact of
competitive products and pricing; the risk that its current and future products
may contain errors or be affected by technical problems that would be difficult
and costly to detect and correct; reliance on a limited number of outside
vendors for key components and processes; potential difficulties in managing
changing business conditions; dependence on key personnel; the availability of
financing; and other risks described in CTS' filings with the Securities and
Exchange Commission.

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