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                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549

                                    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 7, 1999



                                NMT Medical, Inc.
               --------------------------------------------------
               (Exact Name of Registrant as Specified in Charter)


        Delaware                      0-21001                    95-4090463
-------------------------           -----------              ------------------
(State or Other Juris-              (Commission                (IRS Employer
diction of Incorporation)            File No.)               Identification No.)


27 Wormwood Street
Boston, Massachusetts                                             02210
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(Address of Principal Executive Offices)                        (Zip Code)



Registrant's telephone number, including area code       (617) 737-0930
                                                     ----------------------

                       Nitinol Medical Technologies, Inc.
          -------------------------------------------------------------
          (Former name or former address, if changed since last report)


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Item 5.  Other Events.
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     On May 26, 1999, the Board of Directors of NMT Medical, Inc. (formerly
Nitinol Medical Technologies, Inc., and hereinafter, the "Company"), declared a
dividend of one Right for each outstanding share of the Company's Common Stock
to stockholders of record at the close of business on June 10, 1999 (the "Record
Date"). Each Right entitles the registered holder to purchase from the Company
one one-thousandth of a share of Series A Junior Participating Preferred Stock,
$.001 par value per share (the "Preferred Stock"), at a Purchase Price of $20.00
in cash, subject to adjustment. The description and terms of the Rights are set
forth in a Rights Agreement dated as of June 7, 1999 (the "Rights Agreement")
between the Company and American Stock Transfer & Trust Company, as Rights
Agent.

     Initially, the Rights will be attached to all Common Stock certificates
representing shares then outstanding, and no separate Rights Certificates will
be distributed. The Rights will separate from the Common Stock and a
Distribution Date will occur upon the earlier of (i) 10 business days (or such
later date as may be determined by the Board of Directors of the Company)
following the later of (a) a public announcement that a person or group of
affiliated or associated persons (an "Acquiring Person") has acquired, or
obtained the right to acquire, beneficial ownership of 15% or more of the
outstanding shares of Common Stock (or, in the case of Whitney Equity Partners,
L.P. and its affiliates, more than 25% of the outstanding shares of Common
Stock) or (b) the first date on which an executive officer of the Company has
actual knowledge that an Acquiring Person has become such (the "Stock
Acquisition Date"), or (ii) 10 business days (or such later date as may be
determined by the Board of Directors of the Company) following the commencement
of a tender offer or exchange offer that would result in a person or group
beneficially owning 15% or more of such outstanding shares of Common Stock.
Until the Distribution Date (or earlier redemption or expiration of the Rights),
(i) the Rights will be evidenced by the Common Stock certificates and will be
transferred with and only with such Common Stock certificates, (ii) new Common
Stock certificates issued after the Record Date will contain a notation
incorporating the Rights Agreement by reference and (iii) the surrender for
transfer of any certificates for Common Stock outstanding, even without such
notation, will also constitute the transfer of the Rights associated with the
Common Stock represented by such certificate.

     The Rights are not exercisable until the Distribution Date and will expire
upon the close of business on June 9, 2009 (the "Final Expiration Date") unless
earlier redeemed or exchanged as described below. As soon as practicable after
the Distribution Date, separate Rights Certificates will be mailed to holders of
record of the Common Stock as of the close of business on the Distribution Date
and, thereafter, the separate Rights Certificates alone will represent the
Rights. Except as otherwise determined by the Board of Directors, and except for
shares of Common Stock issued upon exercise, conversion or exchange of then
outstanding options, convertible or exchangeable securities or other

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contingent obligations to issue shares, only shares of Common Stock issued prior
to the Distribution Date will be issued with Rights.

     In the event that any Person becomes an Acquiring Person, then, promptly
following the first occurrence of such event, each holder of a Right (except as
provided below and in Section 7(e) of the Rights Agreement) shall thereafter
have the right to receive, upon exercise, that number of shares of Common Stock
of the Company (or, in certain circumstances, cash, property or other securities
of the Company) which equals the exercise price of the Right divided by 50% of
the current market price (as defined in the Rights Agreement) per share of
Common Stock at the date of the occurrence of such event. However, Rights are
not exercisable following such event until such time as the Rights are no longer
redeemable by the Company as described below. Notwithstanding any of the
foregoing, following the occurrence of such event, all Rights that are, or
(under certain circumstances specified in the Rights Agreement) were,
beneficially owned by any Acquiring Person will be null and void. The event
summarized in this paragraph is referred to as a "Section 11(a)(ii) Event."

     In the event that, at any time after any Person becomes an Acquiring
Person, (i) the Company is consolidated with, or merged with and into, another
entity and the Company is not the surviving entity of such consolidation or
merger or if the Company is the surviving entity, but shares of its outstanding
Common Stock are changed or exchanged for stock or securities (of any other
person) or cash or any other property, or (ii) 50% or more of the Company's
assets or earning power is sold or transferred, each holder of a Right (except
Rights which previously have been voided as set forth above) shall thereafter
have the right to receive, upon exercise, that number of shares of common stock
of the acquiring company which equals the exercise price of the Right divided by
50% of the current market price of such common stock at the date of the
occurrence of the event. The events summarized in this paragraph are referred to
as "Section 13 Events." A Section 11(a)(ii) Event and Section 13 Events are
collectively referred to as "Triggering Events."

     At any time after the occurrence of a Section 11(a)(ii) Event, subject to
certain conditions, the Board of Directors of the Company may exchange the
Rights (other than Rights owned by such Acquiring Person which have become
void), in whole or in part, at an exchange ratio of one share of Common Stock,
or one-thousandth of a share of Preferred Stock (or of a share of a class or
series of the Company's preferred stock having equivalent rights, preferences
and privileges), per Right (subject to adjustment).

     The Purchase Price payable, and the number of units of Preferred Stock or
other securities or property issuable, upon exercise of the Rights are subject
to adjustment from time to time to prevent dilution (i) in the event of a stock
dividend on, or a subdivision, combination or reclassification of, the Preferred
Stock, (ii) if holders of the Preferred Stock are granted certain rights or
warrants to subscribe for Preferred Stock or convertible securities at less than
the then-current market price of the Preferred Stock,

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or (iii) upon the distribution to holders of the Preferred Stock of evidences of
indebtedness or assets (excluding regular periodic cash dividends paid out of
earnings or retained earnings) or of subscription rights or warrants (other than
those referred to above). The number of Rights associated with each share of
Common Stock is also subject to adjustment in the event of a stock split of the
Common Stock or a stock dividend on the Common Stock payable in Common Stock or
subdivisions, consolidations or combinations of the Common Stock occurring, in
any such case, prior to the Distribution Date.

     With certain exceptions, no adjustment in the Purchase Price will be
required until cumulative adjustments amount to at least 1% of the Purchase
Price. No fractional shares of Preferred Stock (other than fractions which are
integral multiples of one one-thousandth of a share of Preferred Stock) will be
issued and, in lieu thereof, an adjustment in cash will be made based on the
market price of the Preferred Stock on the last trading date prior to the date
of exercise.

     Preferred Stock purchasable upon exercise of the Rights will not be
redeemable. Each share of Preferred Stock will be entitled to receive, when, as
and if declared by the Board of Directors, a minimum preferential quarterly
dividend payment of $10 per share or, if greater, an aggregate dividend of 1,000
times the dividend declared per share of Common Stock. In the event of
liquidation, the holders of the Preferred Stock will be entitled to a minimum
preferential liquidation payment of $1,000 per share and will be entitled to an
aggregate payment of 1,000 times the payment made per share of Common Stock.
Each share of Preferred Stock will have 1,000 votes, voting together with the
Common Stock. In the event of any merger, consolidation or other transaction in
which Common Stock is changed or exchanged, each share of Preferred Stock will
be entitled to receive 1,000 times the amount received per share of Common
Stock. These rights are protected by customary antidilution provisions. Because
of the nature of the Preferred Stock's dividend, liquidation and voting rights,
the value of one one-thousandth of a share of Preferred Stock purchasable upon
exercise of each Right should approximate the value of one share of Common
Stock.

     At any time prior to the earlier of (i) the tenth Business Day (or such
later date as may be determined by the Board of Directors of the Company) after
the Stock Acquisition Date, or (ii) the Final Expiration Date, the Company may
redeem the Rights in whole, but not in part, at a price of $.001 per Right (the
"Redemption Price"), payable in cash or stock. Immediately upon the action of
the Board of Directors ordering redemption of the Rights, the Rights will
terminate and the only right of the holders of Rights will be to receive the
Redemption Price. The Rights may also be redeemable following certain other
circumstances specified in the Rights Agreement.

     Until a Right is exercised, the holder thereof, as such, will have no
rights as a stockholder of the Company, including, without limitation, the right
to vote or to receive dividends. While the distribution of the Rights will not
be taxable to stockholders or to

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the Company, stockholders may, depending upon the circumstances, recognize
taxable income in the event that the Rights become exercisable for Common Stock
(or other consideration) of the Company or for common stock of the acquiring
company as set forth above.

     Subject to certain exceptions, any of the provisions of the Rights
Agreement may be amended by the Board of Directors of the Company prior to such
time as the Rights are no longer redeemable.

     The foregoing description of the Rights does not purport to be complete and
is qualified in its entirety by reference to the Rights Agreement, dated as of
June 7, 1999, between the Company and the Rights Agent, which includes as
Exhibit A, the form of Certificate of Designation, as Exhibit B, the form of
Rights Certificate , and as Exhibit C, the Summary of Rights to Purchase
Preferred Stock, a copy of the form of which Rights Agreement is filed herewith
as Exhibit 4.1.

Item 7.  Financial Statements, Pro Forma Financial Information and Exhibits.
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                    (c)  Exhibits

Exhibit No.                                   Exhibit
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   4.1              Form of Rights Agreement, dated as of June 7, 1999, between
                    NMT Medical, Inc. and American Stock Transfer & Trust
                    Company, as Rights Agent, which includes as Exhibit A, the
                    form of Certificate of Designation, as Exhibit B, the form
                    of Rights Certificate, and as Exhibit C, the Summary of
                    Rights to Purchase Preferred Stock.

  99.1              Press Release, dated May 27, 1999, announcing adoption of
                    the Stockholder Rights Plan.

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                                   SIGNATURES

     Pursuant to the requirements of the Securities Exchange Act of 1934, the
registrant has duly caused this report to be signed on its behalf by the
undersigned thereunto duly authorized.

Date: June 7, 1999                             NMT Medical, Inc.



                                               By: /s/ Thomas M. Tully
                                                   ----------------------------
                                                   Name:  Thomas M. Tully
                                                   Title:  President

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