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                                                                  Exhibit 4.6

                          REGISTRATION RIGHTS AGREEMENT

         This Registration Rights Agreement, dated as of this 12th day of
October, 2000 (this "Agreement"), is by and among PRI Automation, Inc., a
Massachusetts corporation ("Parent"), and John Tenney (the "Shareholder").

         WHEREAS, pursuant to an Agreement and Plan of Merger dated as of
October 12, 2000, by and among Parent, CTI Acquisition Corp., a Massachusetts
corporation and subsidiary of Parent ("Merger Sub"), Commotion Technology, Inc.,
a California corporation (the "Company'), and the Shareholder (the "Merger
Agreement"), the parties thereto have agreed, subject to the terms and
conditions set forth therein, to merge the Company with and into Merger Sub (the
"Merger") and thereby to convert all shares of Company Common Stock (as such
term is defined in the Merger Agreement) then outstanding into shares of Parent
Stock (as such term is defined in the Merger Agreement);

         WHEREAS, pursuant to a Stock Repurchase Agreement dated as of October
12, 2000 by and between Parent and the Shareholder (the "Stock Repurchase
Agreement"), the shares of Parent Stock received by the Shareholder will be
subject to certain transfer restrictions and a right of repurchase by Parent
until such shares have become Vested Shares (as defined in the Stock Purchase
Agreement);

         WHEREAS, the Shareholder desires to have liquidity with respect to the
shares of Parent Stock he receives in the Merger;

         WHEREAS, Parent desires to grant the Shareholder registration rights as
provided herein; and

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

         1. DEFINITIONS OF CERTAIN TERMS. As used herein, the following terms
         shall have the following meanings:

         Exchange Act: the Securities Exchange Act of 1934, as amended, and the
         rules and regulations of the SEC issued thereunder, as they may, from
         time to time, be in effect.

         Holder: the Shareholder, so long as he holds Registerable Shares, and
         any other person or entity holding Registerable Shares to whom the
         registration rights granted in this Agreement have been transferred
         pursuant to Section 9 hereof.

         Registerable Shares: the shares of Parent Stock issued to the
         Shareholder pursuant to the Merger, and any other securities issued by
         Parent as a dividend or other distribution with respect to, or in
         exchange for or in replacement of, such shares; PROVIDED, HOWEVER,
         Registerable Shares shall not include shares of Parent Stock that (a)
         have been registered under the Securities Act and disposed of pursuant
         to the registration statement used to effect such registration, (b)
         have
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         been sold in the public securities markets in the United States of
         America, (c) are eligible to be sold under Rule 144 under the
         Securities Act, or (d) will not, by the terms of the Stock Repurchase
         Agreement, become Vested Shares before such shares will be eligible to
         be sold under Rule 144.

         SEC: the United States Securities and Exchange Commission, or any
         governmental agency succeeding to its functions.

         Securities Act: the Securities Act of 1933, as amended, and the rules
         and regulations of the SEC issued thereunder, as they may, from time to
         time, be in effect.

         Capitalized terms used, but not otherwise defined, in this Agreement
shall have the meanings given to them in the Merger Agreement.

         Where this Agreement requires Parent to use "best efforts" to satisfy
an obligation or requirement under this Agreement, the parties agree that this
shall not require Parent to make any payment that would not ordinarily be made
in the course of filing, and seeking and maintaining the effectiveness of, a
registration statement similar to the Shelf Registration (as hereinafter
defined).

         2. SHELF REGISTRATION. Parent agrees that, within forty-five (45) days
of the Closing of the Merger, it shall cause to be filed a registration
statement (a "Shelf Registration") on Form S-3 under the Securities Act for an
offering to be made on a delayed or continuous basis pursuant to Rule 415
thereunder or any similar rule that may be adopted by the SEC and permitting
sales in ordinary course brokerage or dealer transactions not involving any
underwritten public offering covering all of the Registerable Shares. Parent
shall use best efforts thereafter (a) to cause the Shelf Registration to be
declared effective by the SEC and (b) subject to Section 3 hereof, to keep the
Shelf Registration continuously effective until the earlier of (i) the first
date on which no Registrable Shares originally covered by the Shelf Registration
shall constitute Registrable Shares, or (ii) the first anniversary of the
Closing (such period is referred to herein as the "Registration Period").

         3. REGISTRATION PROCEDURES. After Parent commences the registration of
the Registrable Shares pursuant to the Shelf Registration, Parent shall:

            (a) furnish to the Holder such number of copies of the Shelf
Registration, each amendment and supplement thereto (in each case including all
exhibits thereto), the prospectus included in the Shelf Registration (including
any preliminary prospectus) and such other documents as the Holder may
reasonably request in order to facilitate the disposition of the Registrable
Shares owned by the Holder;

            (b) use best efforts to register or qualify such Registrable Shares
under such other securities or "blue sky" laws of such jurisdictions as the
Holder reasonably requests in writing and to do any and all other acts and
things that may be reasonably necessary or advisable to register or qualify for
sale in such jurisdictions the Registrable Shares owned by the Holder; PROVIDED,
HOWEVER, that Parent shall not be required (i) to

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qualify to do business in any jurisdiction where it is not then so qualified or
(ii) to consent to general service of process in any jurisdiction where it is
not then so subject to service of process; and

            (c) use best efforts to cause all Registrable Shares covered by the
Shelf Registration to be listed on the primary securities exchange or market, if
any, on which similar securities issued by Parent are then listed, PROVIDED that
the applicable listing requirements are satisfied.

         4. PARENT REGISTRATION.

            (a) At any time during the Registration Period that the Shelf
Registration is not effective under Section 2, the Holder shall have the
following rights under this Section 4. If Parent shall determine to register any
shares of Company Common Stock in addition to the shares of Company Common Stock
registered pursuant to the Shelf Registration either for its own account or the
account of a security holder or holders exercising their respective demand
registration rights, other than a registration relating solely to employee
benefit plans, or a registration relating solely to a Rule 145 transaction, or a
registration on any registration form that does not permit secondary sales,
Parent will:

                (i) promptly give to the Holder written notice thereof pursuant
to Section 14; and

                (ii) use its best efforts to include in such registration (and
any related qualification under blue sky laws or other compliance), and in any
underwriting involved therein, all the Registrable Shares specified in a written
request or requests, made by the Holder and received by Parent within ten (10)
days after the written notice from Parent described in clause (i) above is
mailed or delivered by Parent. Such written request may specify all or a part of
the Holder's Registrable Shares.

             (b) If the registration of which Parent gives notice is for a
registered public offering involving an underwriting, Parent shall so advise the
Holder as a part of a written notice given pursuant to Section 14. In such
event, the right of any Holder to registration pursuant to this Section 4 shall
be conditioned upon such Holder's participation in such underwriting and the
inclusion of such Holder's Registrable Shares in the underwriting to the extent
provided herein. Should Holder wish to participate in such a registration, The
Holder agrees that he shall (together with Parent and the other holders of
securities of Parent with registration rights to participate therein
distributing their securities through such underwriting) enter into an
underwriting agreement in customary form with the representative of the
underwriter or underwriters selected by Parent.

             (c) Notwithstanding any other provision of this Section 4 if the
representative of the underwriters advises Parent in writing that marketing
factors require a limitation on the number of shares to be underwritten, the
representative may exclude all Registrable Shares from, or limit the number of
Registrable Shares to be included in, the registration and underwriting. If the
offering of Parent's securities are to the general public, Parent

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may limit, to the extent so advised by the underwriters, the amount of
securities to be included in the registration by Parent's shareholders
(including the Holder); provided, however, that the aggregate value of
securities to be included in such registration by Parent's shareholders
(including the Holder) may not be so reduced to less than twenty-five percent
(25%) of the total value of all securities included in such registration. Parent
shall so advise the Holder, and the number of shares of securities that are
entitled to be included in the registration and underwriting shall be allocated
first to Parent for securities being sold for its own account and thereafter as
set forth herein. If any person does not agree to the terms of any such
underwriting, he shall be excluded therefrom by written notice from Parent or
the underwriter. Any Registrable Shares or other securities excluded or
withdrawn from such underwriting shall be withdrawn from such registration.

         5. STOP ORDER; SUPPLEMENT TO THE PROSPECTUS; PARENT'S INSIDER TRADING
POLICIES.

             (a) Parent will notify the Holder promptly of (i) the issuance of
any stop order suspending the effectiveness of the Shelf Registration or the
institution or threatening of any proceeding for such purpose or (ii) the
receipt by Parent of any notification with respect to the suspension of the
qualification of the Registrable Shares for sale in any jurisdiction or the
initiation or threatening of any proceeding for such purpose. Immediately upon
receipt of any such notice, the Holder shall cease to offer and sell any
Registrable Shares pursuant to the Shelf Registration in the jurisdiction to
which such stop order or suspension relates. Parent shall use best efforts to
prevent the issuance of any such stop order or the suspension of any such
qualification and, if any such stop order is issued or any such qualification is
suspended, to obtain as soon as possible the withdrawal or revocation thereof,
and will notify the Holder at the earliest practicable date of the date on which
the Holder may offer and sell Registrable Shares pursuant to the Shelf
Registration.

             (b) Parent will notify the Holder promptly of the occurrence of any
event or the existence of any state of facts that, in the judgment of Parent,
should be set forth in the prospectus used in connection with the Shelf
Registration (the "Prospectus"). Immediately upon receipt of such notice, the
Holder shall cease to offer or sell any Registrable Shares pursuant to such
Prospectus, cease to deliver or use such Prospectus and, if so requested by
Parent, return to Parent, at its expense, all copies (other than permanent file
copies) of such Prospectus. Parent will, as soon as the information becomes
available in a form such that it may be included in an amendment or supplement
to the Prospectus, use best efforts to amend or supplement such Prospectus in
order to set forth or reflect such event or state of facts; IT BEING UNDERSTOOD
that in the event that Parent determines in good faith that the disclosure of
such information would be seriously detrimental to Parent or its shareholders,
Parent shall be permitted to delay the filing of such an amendment or supplement
to the Prospectus for a period of time to extend no longer than forty-five (45)
days. Parent will furnish copies of such amendment or supplement to the
Prospectus to the Holder.

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             (c) The Holder agrees, if and for so long as the Holder is an
employee of Parent or any of Parent's Subsidiaries, to comply with any Parent
policy concerning the purchase and sale of securities of Parent.

         6. INFORMATION CONCERNING THE SELLERS.

         (a) The obligations of Parent to take actions contemplated by Sections
2, 3 and 4 hereof with respect to an offering of Registrable Shares shall be
subject to the condition that the Holder shall (i) conform to all applicable
requirements of the Securities Act and the Exchange Act with respect to the
offering and sale of securities and (ii) advise each underwriter, broker or
dealer through which any of such Registrable Shares are offered that such
Registrable Shares are part of a distribution that is subject to the prospectus
delivery requirements of the Securities Act, and the Holder shall furnish to
Parent in writing such information and furnish such documents as may be
reasonably required by Parent in the preparation of (A) the Prospectus (or any
amendment or supplement thereto) with respect to such offering and (B) any
qualification of such Registrable Shares under state securities or "blue sky"
laws pursuant to Section 3(b) hereof, and shall promptly notify Parent of the
occurrence, from the date on which such information or documents are furnished
to the date of the closing for the sale of such Registrable Shares, of any event
relating to the Holder that is required under the Securities Act to be set forth
in the Prospectus (or any amendment or supplement thereto).

         (b) At the end of the Registration Period the Holder shall discontinue
sales of Registrable Shares pursuant to the Shelf Registration after Parent has
given notice to the Holder of its intention to remove from registration the
securities covered by the Registration Statement which remain unsold, and the
Holder shall notify Parent immediately upon receipt of such notice from Parent
of the number of shares of the Holder that are registered but remain unsold.

         7. EXPENSES OF REGISTRATION. Parent shall pay all reasonable expenses
incident to its performance of or compliance with this Agreement and
registration of Registrable Shares in connection herewith, including (a) all
SEC, stock exchange or market and National Association of Securities Dealers,
Inc. registration and filing fees, (b) all fees and expenses incurred in
complying with securities or "blue sky" laws, (c) all printing, messenger and
delivery expenses, (d) all fees and disbursements of Parent's independent public
accountants and counsel, and (e) the reasonable fees and expenses of one counsel
to the Holder, not to exceed $2,500 (all of such expenses herein referred to s
"Registration Expenses"). The Registration Expenses shall not include any sales
or underwriting discounts, commissions or fees attributable to the sale of the
Registrable Shares, which shall be borne by the Holder.

         8. DISCLOSURE. With a view to making available registration on Form S-3
and the benefits of Rule 144 under the Securities Act, Parent agrees to:

         (a) Make and keep current public information available within the
meaning of Rule 144(c).

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         (b) File with the SEC in a timely manner all reports and other
documents and information required of Parent under the Exchange Act, and take
such other actions as may be necessary to assure the availability of Form S-3
for use in connection with the registration rights provided in this Agreement.

         (c) Furnish to the Holder forthwith upon request a written statement as
to Parent's compliance with the reporting requirements of Rule 144 and the
Exchange Act, a copy of Parent's most recent annual and quarterly reports, and
such other reports, documents and other information in the possession of or
reasonably obtainable by Parent as the Holder may reasonably request in availing
itself of Rule 144.

         9. INDEMNIFICATION AND CONTRIBUTION.

         (a) Parent agrees to indemnify, to the extent permitted by law and
subject to the terms of this Agreement, the Holder and each person, if any, who
controls the Holder (within the meaning of the Securities Act) against any
losses, claims, damages, liabilities and expenses (including reasonable
attorneys' fees) arising out of or based upon any untrue or alleged untrue
statement of a material fact contained in the Shelf Registration (or any
amendment thereto) or the Prospectus (or any amendment or supplement thereto) or
any omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements made therein in the light of
the circumstances under which they were made not misleading; PROVIDED, HOWEVER,
that Parent shall not be liable to the Holder and each person, if any, who
controls the Holder (within the meaning of the Securities Act) to the extent
that any such loss, claim, damage, liability or expense arises out of, or is
based upon any untrue or alleged untrue statement, or any omission, if such
statement or omission shall have been made in reliance upon and in conformity
with information relating to the Holder or person furnished in writing to Parent
by any the Holder or person expressly for use in the preparation of the Shelf
Registration (or any amendment thereto) or the Prospectus (or any amendment or
supplement thereto).

         (b) In connection with the Shelf Registration, the Holder agrees to
indemnify, to the extent permitted by law and subject to the terms of this
Agreement, Parent, its directors, officers, employees and agents and each person
who controls Parent (within the meaning of the Securities Act) against any
losses, claims, damages, liabilities and expenses (including reasonable
attorneys' fees) arising out of or based upon any untrue or alleged untrue
statement of a material fact contained in the Shelf Registration (or any
amendment thereto) or the Prospectus (or any amendment or supplement thereto) or
any omission or alleged omission to state therein a material fact required to be
stated therein or necessary to make the statements made therein in the light of
the circumstances under which they were made not misleading, to the extent that
such untrue statement or omission was made in reliance upon and in conformity
with information furnished in writing to Parent by the Holder expressly for use
in the preparation of the Shelf Registration (or any amendment thereto) or the
Prospectus (or any amendment or supplement thereto).

         (c) Each party entitled to indemnification under this Section 8 shall
give notice to the party required to provide indemnification promptly after such
indemnified

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party has actual knowledge of any claim as to which indemnity may be sought, and
shall permit the indemnifying party to assume the defense of any such claim or
any litigation resulting therefrom; PROVIDED that counsel for the indemnifying
party, who shall conduct the defense of such claim or litigation, shall be
approved by the indemnified party (whose approval shall not be unreasonably
withheld or delayed); and PROVIDED, FURTHER, that the delay or failure of any
indemnified party to give notice as provided herein shall not relieve the
indemnifying party of its obligations under this Section 8, except to the extent
that the indemnifying party shall have been materially adversely affected by
such delay or failure. The indemnified party may participate in such defense at
such party's expense; PROVIDED, HOWEVER, that the indemnifying party shall pay
such expense if the indemnified party shall have reasonably concluded that there
may be a conflict between the positions of the indemnifying party and the
indemnified party in conducting the defense of any such claim or litigation
resulting therefrom. No indemnified party shall consent to entry of any judgment
or settle any claim or litigation without the prior written consent of the
indemnifying party.

         (d) If the indemnification provided for in this Section 8 from the
indemnifying party is unavailable to an indemnified party hereunder in respect
of any losses, claims, damages, liabilities or expenses referred to therein as a
result of a judicial determination that such indemnification may not be enforced
in such case notwithstanding this Agreement, the indemnifying party, in lieu of
indemnifying such indemnified party, shall contribute to the amount paid or
payable by such indemnified party as a result of such losses, claims, damages,
liabilities or expenses in such proportion as is appropriate to reflect the
relative fault of the indemnifying party and indemnified parties in connection
with the actions which resulted in such losses, claims, damages, liabilities or
expense, as well as any other relevant equitable considerations. The relative
fault of such indemnifying party and indemnified parties shall be determined by
reference to, among other things, whether any action in question, including any
untrue or alleged untrue statement of material fact or omission or alleged
omission to state a material fact, has been made by, or relates to information
supplied by, such indemnifying party or indemnified parties, and the parties'
relative intent, knowledge, access to information and opportunity to correct or
prevent such action. No person guilty of fraudulent misrepresentation (within
the meaning of Section 11(f) of the Securities Act) shall be entitled to
contribution from any person who was not guilty of such fraudulent
misrepresentation.

         10. TRANSFER OF REGISTRATION RIGHTS. The registration rights of the
Holder (and of any transferee of the Holder or its transferees) under this
Agreement with respect to any Registrable Shares may be transferred to any
transferee of such Registrable Shares; PROVIDED that Parent is given written
notice by the Holder at the time of such transfer stating the name and address
of the transferee and identifying the Registrable Shares with respect to which
the rights under this Agreement are being assigned and such transferee executes
and delivers such agreements as Parent may reasonably require in order to
confirm that such transferee agrees to be bound by this Agreement.

         11. AMENDMENTS AND SUPPLEMENTS. This Agreement may not be amended,
modified or supplemented by the parties hereto in any manner, except by an
instrument in writing signed by Parent and the Shareholder.

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         12. NO WAIVER. The terms and conditions of this Agreement may be waived
only by a written instrument signed by (a) the Shareholder in the case where the
Shareholder is waiving compliance and (b) by Parent in the case where Parent is
waiving compliance. The failure of any party hereto to enforce at any time any
of the provisions of this Agreement shall in no way be construed to be a waiver
of any such provision, nor in any way to affect the validity of this Agreement
or any part hereof or the right of such party thereafter to enforce each and
every such provision. No waiver of any breach of or non-compliance with this
Agreement shall be held to be a waiver of any other or subsequent breach or
non-compliance. The rights and remedies herein provided are cumulative and are
not exclusive of any rights or remedies that any party may otherwise have at law
or in equity.

         13. GOVERNING LAW. This Agreement shall be governed by, and construed
and enforced in accordance with, the substantive laws of the Commonwealth of
Massachusetts, without regard to its principles of conflicts of laws.

         14. NOTICE. All notices and other communications hereunder shall be in
writing and shall be deemed given if delivered by hand, sent by facsimile
transmission with confirmation of receipt, sent via a reputable overnight
courier service with confirmation of receipt requested, or mailed by registered
or certified mail (postage prepaid and return receipt requested) to the parties
at the following addresses (or at such other address for a party as shall be
specified by like notice), and shall be deemed given on the date on which
delivered by hand or otherwise on the date of receipt as confirmed:

         TO PARENT:

                  PRI Automation, Inc.
                  805 Middlesex Turnpike
                  Billerica, Massachusetts 01821
                  Facsimile: (508) 671-9430
                  Attention: President

         With a copy to:

                  Robert L. Birnbaum, Esq.
                  Foley, Hoag & Eliot LLP
                  One Post Office Square
                  Boston, Massachusetts 02109
                  Facsimile: (617) 832-7000

         TO THE HOLDER:

                  John Tenney
                  1412 Grand Avenue
                  Piedmont, California  94610

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         With a copy to:

                  Kevin W. Finck
                  Two Embarcadero Center, Ste. 1670
                  San Fransisco, California  94111
                  Facsimile:  (415) 394-6446

         15. CONSTRUCTION OF AGREEMENT. A reference to a Section shall mean a
Section in this Agreement unless otherwise expressly stated. The titles and
headings herein are for reference purposes only and shall not in any manner
limit the construction of this Agreement which shall be considered as a whole.
The words "include," "includes" and "including" when used herein shall be deemed
in each case to be followed by the words "without limitation."

         16. ENTIRE AGREEMENT, ASSIGNABILITY, ETC.. This Agreement and the
Merger Agreement and the documents and other agreements among the parties hereto
and thereto as contemplated by or referred to herein or therein constitute the
entire agreement among the parties with respect to the subject matter hereof and
supersede all other prior agreements and understandings, both written and oral,
between the parties with respect to the subject matter hereof. This Agreement
shall be binding upon and inure to the benefit of the parties hereto and their
respective successors and permitted assigns. This Agreement is not intended to
confer upon any person other than the parties hereto any rights or remedies
hereunder, except as otherwise expressly provided herein and shall not be
assignable by operation of law or otherwise, except as provided in Section 9
hereof.

         17. VALIDITY. The invalidity or unenforceability of any provision of
this Agreement shall not affect the validity or enforceability of any other
provision of this Agreement, each of which shall remain in full force and
effect.

         18. COUNTERPARTS. This Agreement may be executed in one or more
counterparts, all of which together shall constitute one and the same Agreement.

         19. PROFESSIONAL FEES. In the event of the bringing of any claim,
action, suit or arbitration by a party hereto against another party hereunder by
reason of any breach of any of the covenants, agreements, or provisions arising
out of this Agreement, the prevailing party shall be entitled to recover all
costs and expenses of that claim, action, suit or arbitration, at trial,
arbitration or on appeal and in collection of judgment, including but not
limited to reasonable attorneys', accounting, and other professional fees
resulting therefrom.

                                    * * * * *

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         IN WITNESS WHEREOF, the parties have caused this Registration Rights
Agreement to be executed as an agreement under seal as of the date first written
above.

                                                   PRI AUTOMATION, INC.

                                                   By: /s/ Cosmo Trapani
                                                       ------------------------
                                                       Title: VP & CFO

                                                       /s/ John Tenney
                                                       ------------------------
                                                       John Tenney


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