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                                                                   Exhibit 10.12

                              AMENDED AND RESTATED

                           COGENT COMMUNICATIONS GROUP

                           2000 EQUITY INCENTIVE PLAN


     1. PURPOSES OF THE PLAN. The purposes of the Cogent Communications Group
2000 Equity Incentive Plan are to attract and retain the best available
personnel for positions of substantial responsibility, to provide additional
incentive to Employees, Directors and Consultants and to promote the success of
the Company's business. Options granted under the Plan may be Incentive Stock
Options or Non-Qualified Stock Options, as determined by the Administrator at
the time of grant, subject to Applicable Laws. Stock Purchase Rights may also be
granted under the Plan.

     2. DEFINITIONS. As used herein, the following definitions shall apply:

        (a) "ACQUISITION" means (i) any consolidation or merger of the Company
with or into any other corporation or other entity or person in which the
stockholders of the Company prior to such consolidation or merger own less than
fifty percent (50%) of the Company's voting power immediately after such
consolidation or merger, excluding any consolidation or merger effected
exclusively to change the domicile of the Company; or (ii) a sale of all or
substantially all of the assets of the Company.

        (b) "ADMINISTRATOR" means the Board or the Committee responsible for
conducting the general administration of the Plan, as applicable, in accordance
with Section 4 hereof.

        (c) "APPLICABLE LAWS" means the requirements relating to the
administration of stock option plans under U.S. state corporate laws, U.S.
federal and state securities laws, the Code, any stock exchange or quotation
system on which the Common Stock is listed or quoted and the applicable laws of
any foreign country or jurisdiction where Options or Stock Purchase Rights are
granted under the Plan.

        (d) "BOARD" means the Board of Directors of the Company.

        (e) "CODE" means the Internal Revenue Code of 1986, as amended.

        (f) "COMMITTEE" means a committee appointed by the Board in accordance
with Section 4 hereof.

        (g) "COMMON STOCK" means the Common Stock of the Company, par value
$.001 per share.


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        (h) "COMPANY" means Cogent Communications Group Inc., a Delaware
corporation.

        (i) "CONSULTANT" means any consultant or adviser if: (i) the consultant
or adviser renders bona fide services to the Company; (ii) the services rendered
by the consultant or adviser are not in connection with the offer or sale of
securities in a capital-raising transaction and do not directly or indirectly
promote or maintain a market for the Company's securities; and (iii) the
consultant or adviser is a natural person who has contracted directly with the
Company to render such services.

        (j) "DIRECTOR" means a member of the Board.

        (k) "EMPLOYEE" means any person, including an Officer or Director, who
is an employee (as defined in accordance with Section 3401(c) of the Code) of
the Company or any Parent or Subsidiary of the Company. A Service Provider shall
not cease to be an Employee in the case of (i) any leave of absence approved by
the Company or (ii) transfers between locations of the Company or between the
Company, its Parent, any Subsidiary, or any successor. For purposes of Incentive
Stock Options, no such leave may exceed ninety (90) days, unless reemployment
upon expiration of such leave is guaranteed by statute or contract. Neither
service as a Director nor payment of a director's fee by the Company shall be
sufficient, by itself, to constitute "employment" by the Company.

        (l) "EXCHANGE ACT" means the Securities Exchange Act of 1934, as
amended.

        (m) "FAIR MARKET VALUE" means, as of any date, the value of a share of
Common Stock determined as follows:

            (i) If the Common Stock is listed on any established stock exchange
or a national market system, including, without limitation, the Nasdaq National
Market or The Nasdaq SmallCap Market of The Nasdaq Stock Market, its Fair Market
Value shall be the closing sales price for a share of such stock (or the closing
bid, if no sales were reported) as quoted on such exchange or system for the
last market trading day prior to the time of determination, as reported in The
Wall Street Journal or such other source as the Administrator deems reliable;

            (ii) If the Common Stock is regularly quoted by a recognized
securities dealer but selling prices are not reported, its Fair Market Value
shall be the mean between the high bid and low asked prices for a share of the
Common Stock on the last market trading day prior to the day of determination;
or

            (iii) In the absence of an established market for the Common Stock,
the Fair Market Value thereof shall be determined in good faith by the
Administrator.


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        (n) "HOLDER" means a person who has been granted or awarded an Option or
Stock Purchase Right or who holds Shares acquired pursuant to the exercise of an
Option or Stock Purchase Right.

        (o) "INCENTIVE STOCK OPTION" means an Option intended to qualify as an
incentive stock option within the meaning of Section 422 of the Code and which
is designated as an Incentive Stock Option by the Administrator.

        (p) "INDEPENDENT DIRECTOR" means a Director who is not an Employee of
the Company.

        (q) "NON-QUALIFIED STOCK OPTION" means an Option (or portion thereof)
that is not designated as an Incentive Stock Option by the Administrator, or
which is designated as an Incentive Stock Option by the Administrator but fails
to qualify as an incentive stock option within the meaning of Section 422 of the
Code.

        (r) "OFFICER" means a person who is an officer of the Company within the
meaning of Section 16 of the Exchange Act and the rules and regulations
promulgated thereunder.

        (s) "OPTION" means a stock option granted pursuant to the Plan.

        (t) "OPTION AGREEMENT" means a written agreement between the Company and
a Holder evidencing the terms and conditions of an individual Option grant. The
Option Agreement is subject to the terms and conditions of the Plan.

        (u) "PARENT" means a "parent corporation," whether now or hereafter
existing, as defined in Section 424(e) of the Code.

        (v) "PLAN" means the Cogent Communications Group 2000 Equity Incentive
Plan.

        (w) "PUBLIC TRADING DATE" means the first date upon which Common Stock
of the Company is listed (or approved for listing) upon notice of issuance on
any securities exchange or designated (or approved for designation) upon notice
of issuance as a national market security on an interdealer quotation system.

        (x) "RESTRICTED STOCK" means Shares acquired pursuant to the exercise of
an unvested Option in accordance with Section 10(h) below or pursuant to a Stock
Purchase Right granted under Section 12 below.

        (y) "RULE 16b-3" means that certain Rule 16b-3 under the Exchange Act,
as such Rule may be amended from time to time.

        (z) "SECTION 16(b)" means Section 16(b) of the Exchange Act.


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        (aa) "SECURITIES ACT" means the Securities Act of 1933, as amended.

        (bb) "SERVICE PROVIDER" means an Employee, Director or Consultant.

        (cc) "SHARE" means a share of Common Stock, as adjusted in accordance
with Section 13 below.

        (dd) "STOCK PURCHASE RIGHT" means a right to purchase Common Stock
pursuant to Section 12 below.

        (ee) "SUBSIDIARY" means a "subsidiary corporation," whether now or
hereafter existing, as defined in Section 424(f) of the Code.

     3. STOCK SUBJECT TO THE PLAN. Subject to the provisions of Section 13 of
the Plan, the shares of stock subject to Options or Stock Purchase Rights shall
be Common Stock, initially shares of the Company's Common Stock, par value $.001
per share. Subject to the provisions of Section 13 of the Plan, the maximum
aggregate number of Shares which may be issued upon exercise of such Options or
Stock Purchase Rights is 9,900,000 Shares. Shares issued upon exercise of
Options or Stock Purchase Rights may be authorized but unissued, or reacquired
Shares. If an Option or Stock Purchase Right expires or becomes unexercisable
without having been exercised in full, the unpurchased Shares which were subject
thereto shall become available for future grant or sale under the Plan (unless
the Plan has terminated). Shares which are delivered by the Holder or withheld
by the Company upon the exercise of an Option or Stock Purchase Right under the
Plan, in payment of the exercise price thereof or tax withholding thereon, may
again be optioned, granted or awarded hereunder, subject to the limitations of
this Section 3. If Shares of Restricted Stock are repurchased by the Company at
their original purchase price, such Shares shall become available for future
grant under the Plan. Notwithstanding the provisions of this Section 3, no
Shares may again be optioned, granted or awarded if such action would cause an
Incentive Stock Option to fail to qualify as an Incentive Stock Option under
Code Section 422.

     4. ADMINISTRATION OF THE PLAN.

        (a) ADMINISTRATOR. Unless and until the Board delegates administration
to a Committee as set forth below, the Plan shall be administered by the Board.
The Board may delegate administration of the Plan to a Committee or Committees
of one or more members of the Board, and the term "Committee" shall apply to any
person or persons to whom such authority has been delegated. If administration
is delegated to a Committee, the Committee shall have, in connection with the
administration of the Plan, the powers theretofore possessed by the Board,
including the power to delegate to a subcommittee any of the administrative
powers the Committee is authorized to exercise (and references in this Plan to
the Board shall thereafter be to the Committee or subcommittee), subject,
however, to such resolutions, not inconsistent with the provisions of the Plan,
as may be adopted from time to time by the Board. Notwithstanding the foregoing,
however, from and after the Public Trading Date, a Committee of the Board shall



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administer the Plan and the Committee shall consist solely of two or more
Independent Directors each of whom is both an "outside director," within the
meaning of Section 162(m) of the Code, and a "non-employee director" within the
meaning of Rule 16b-3. Within the scope of such authority, the Board or the
Committee may (i) delegate to a committee of one or more members of the Board
who are not Independent Directors the authority to grant awards under the Plan
to eligible persons who are either (A) not then "covered employees," within the
meaning of Section 162(m) of the Code and are not expected to be "covered
employees" at the time of recognition of income resulting from such award or (B)
not persons with respect to whom the Company wishes to comply with Section
162(m) of the Code and/or (ii) delegate to a committee of one or more members of
the Board who are not "non-employee directors," within the meaning of Rule
16b-3, the authority to grant awards under the Plan to eligible persons who are
not then subject to Section 16 of the Exchange Act. The Board may abolish the
Committee at any time and revest in the Board the administration of the Plan.
Appointment of Committee members shall be effective upon acceptance of
appointment. Committee members may resign at any time by delivering written
notice to the Board. Vacancies in the Committee may only be filled by the Board.

        (b) POWERS OF THE ADMINISTRATOR. Subject to the provisions of the Plan
and the specific duties delegated by the Board to such Committee, and subject to
the approval of any relevant authorities, the Administrator shall have the
authority in its discretion to:

            (i) Determine the Fair Market Value;

            (ii) Select the Service Providers to whom Options and Stock Purchase
Rights may from time to time be granted hereunder;

            (iii) Determine the number of Shares to be covered by each such
award granted hereunder;

            (iv) Approve forms of agreement for use under the Plan;

            (v) Determine the terms and conditions of any Option or Stock
Purchase Right granted hereunder (such terms and conditions include, but are not
limited to, the exercise price, the time or times when Options or Stock Purchase
Rights may vest or be exercised (which may be based on performance criteria),
any vesting acceleration or waiver of forfeiture restrictions, and any
restriction or limitation regarding any Option or Stock Purchase Right or the
Common Stock relating thereto, based in each case on such factors as the
Administrator, in its sole discretion, shall determine);

            (vi) Determine whether to offer to buyout a previously granted
Option as provided in subsection 10(i) and to determine the terms and conditions
of such offer and buyout (including whether payment is to be made in cash or
Shares);


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            (vii) Prescribe, amend and rescind rules and regulations relating to
the Plan, including rules and regulations relating to sub-plans established for
the purpose of qualifying for preferred tax treatment under foreign tax laws;

            (viii) Allow Holders to satisfy withholding tax obligations by
electing to have the Company withhold from the Shares to be issued upon exercise
of an Option or Stock Purchase Right that number of Shares having a Fair Market
Value equal to the minimum amount required to be withheld based on the statutory
withholding rates for federal and state tax purposes that apply to supplemental
taxable income. The Fair Market Value of the Shares to be withheld shall be
determined on the date that the amount of tax to be withheld is to be
determined. All elections by Holders to have Shares withheld for this purpose
shall be made in such form and under such conditions as the Administrator may
deem necessary or advisable;

            (ix) Amend the Plan or any Option or Stock Purchase Right granted
under the Plan as provided in Section 15; and

            (x) Construe and interpret the terms of the Plan and awards granted
pursuant to the Plan and to exercise such powers and perform such acts as the
Administrator deems necessary or desirable to promote the best interests of the
Company which are not in conflict with the provisions of the Plan.

        (c) EFFECT OF ADMINISTRATOR'S DECISION. All decisions, determinations
and interpretations of the Administrator shall be final and binding on all
Holders.

     5. ELIGIBILITY. Non-Qualified Stock Options and Stock Purchase Rights may
be granted to Service Providers. Incentive Stock Options may be granted only to
Employees. If otherwise eligible, an Employee or Consultant who has been granted
an Option or Stock Purchase Right may be granted additional Options or Stock
Purchase Rights. Each Independent Director shall be eligible to be granted
Options in the discretion of the Administrator.

     6. LIMITATIONS.

        (a) Each Option shall be designated by the Administrator in the Option
Agreement as either an Incentive Stock Option or a Non-Qualified Stock Option.
However, notwithstanding such designations, to the extent that the aggregate
Fair Market Value of Shares subject to a Holder's Incentive Stock Options and
other incentive stock options granted by the Company, any Parent or Subsidiary,
which become exercisable for the first time during any calendar year (under all
plans of the Company or any Parent or Subsidiary) exceeds $100,000, such excess
Options or other options shall be treated as Non-Qualified Stock Options. For
purposes of this Section 6(a), Incentive Stock Options shall be taken into
account in the order in which they were granted, and the Fair Market Value of
the Shares shall be determined as of the time of grant.


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        (b) Neither the Plan, any Option nor any Stock Purchase Right shall
confer upon a Holder any right with respect to continuing the Holder's
employment or consulting relationship with the Company, nor shall they interfere
in any way with the Holder's right or the Company's right to terminate such
employment or consulting relationship at any time, with or without cause.

        (c) No Service Provider shall be granted, in any calendar year, Options
or Stock Purchase Rights to purchase more than 9,900,000 Shares; PROVIDED,
HOWEVER, that the foregoing limitation shall not apply prior to the Public
Trading Date and, following the Public Trading Date, the foregoing limitation
shall not apply until the earliest of: (i) the first material modification of
the Plan (including any increase in the number of shares reserved for issuance
under the Plan in accordance with Section 3); (ii) the issuance of all of the
shares of Common Stock reserved for issuance under the Plan; (iii) the
expiration of the Plan; (iv) the first meeting of stockholders at which
Directors of the Company are to be elected that occurs after the close of the
third calendar year following the calendar year in which occurred the first
registration of an equity security of the Company under Section 12 of the
Exchange Act; or (v) such other date required by Section 162(m) of the Code and
the rules and regulations promulgated thereunder. The foregoing limitation shall
be adjusted proportionately in connection with any change in the Company's
capitalization as described in Section 13. For purposes of this Section 6(c), if
an Option is canceled in the same calendar year it was granted (other than in
connection with a transaction described in Section 13), the canceled Option will
be counted against the limit set forth in this Section 6(c). For this purpose,
if the exercise price of an Option is reduced, the transaction shall be treated
as a cancellation of the Option and the grant of a new Option.

     7. TERM OF PLAN. The Plan shall become effective upon its initial adoption
by the Board and shall continue in effect until it is terminated under Section
15 of the Plan. No Options or Stock Purchase Rights may be issued under the Plan
after the tenth (10th) anniversary of the earlier of (a) the date upon which the
Plan is adopted by the Board or (b) the date the Plan is approved by the
stockholders.

     8. TERM OF OPTION. The term of each Option shall be stated in the Option
Agreement; PROVIDED, HOWEVER, that the term shall be no more than ten (10) years
from the date of grant thereof. In the case of an Incentive Stock Option granted
to a Holder who, at the time the Option is granted, owns (or is treated as
owning under Code Section 424) stock representing more than ten percent (10%) of
the voting power of all classes of stock of the Company or any Parent or
Subsidiary, the term of the Option shall be five (5) years from the date of
grant or such shorter term as may be provided in the Option Agreement.

     9. OPTION EXERCISE PRICE AND CONSIDERATION.

        (a) The per share exercise price for the Shares to be issued upon
exercise of an Option shall be such price as is determined by the Administrator,
PROVIDED, that in the case of an Incentive Stock Option (i) granted to an
Employee who, at the time of grant of such Option, owns (or is treated as owning
under Code Section 424) stock representing more than ten percent


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(10%) of the voting power of all classes of stock of the Company or any Parent
or Subsidiary, the per Share exercise price shall be no less than one hundred
ten percent (110%) of the Fair Market Value per Share on the date of grant, and
(ii) granted to any other Employee, the per Share exercise price shall be no
less than one hundred percent (100%) of the Fair Market Value per Share on the
date of grant. Notwithstanding the foregoing subsections (i) and (ii), Options
may be granted with a per Share exercise price other than as required above
pursuant to a merger or other corporate transaction.

        (b) The consideration to be paid for the Shares to be issued upon
exercise of an Option, including the method of payment, shall be determined by
the Administrator (and, in the case of an Incentive Stock Option, shall be
determined at the time of grant). Such consideration may consist of (i) cash,
(ii) check, (iii) with the consent of the Administrator, a full recourse
promissory note bearing interest (at no less than such rate as shall then
preclude the imputation of interest under the Code) and payable upon such terms
as may be prescribed by the Administrator, (iv) with the consent of the
Administrator, other Shares which (A) in the case of Shares acquired from the
Company, have been owned by the Holder for more than six (6) months on the date
of surrender, and (B) have a Fair Market Value on the date of surrender equal to
the aggregate exercise price of the Shares as to which such Option shall be
exercised, (v) with the consent of the Administrator, surrendered Shares then
issuable upon exercise of the Option having a Fair Market Value on the date of
exercise equal to the aggregate exercise price of the Option or exercised
portion thereof, (vi) property of any kind which constitutes good and valuable
consideration, (vii) with the consent of the Administrator, delivery of a notice
that the Holder has placed a market sell order with a broker with respect to
Shares then issuable upon exercise of the Options and that the broker has been
directed to pay a sufficient portion of the net proceeds of the sale to the
Company in satisfaction of the Option exercise price, PROVIDED, that payment of
such proceeds is then made to the Company upon settlement of such sale, or
(viii) with the consent of the Administrator, any combination of the foregoing
methods of payment.

     10. EXERCISE OF OPTION.

        (a) VESTING; FRACTIONAL EXERCISES. Options granted hereunder shall be
vested and exercisable according to the terms hereof at such times and under
such conditions as determined by the Administrator and set forth in the Option
Agreement. An Option may not be exercised for a fraction of a Share.

        (b) DELIVERIES UPON EXERCISE. All or a portion of an exercisable Option
shall be deemed exercised upon delivery of all of the following to the Secretary
of the Company or his or her office:

            (i) A written or electronic notice complying with the applicable
rules established by the Administrator stating that the Option, or a portion
thereof, is exercised. The notice shall be signed by the Holder or other person
then entitled to exercise the Option or such portion of the Option;


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            (ii) Such representations and documents as the Administrator, in its
absolute discretion, deems necessary or advisable to effect compliance with
Applicable Laws. The Administrator may, in its absolute discretion, also take
whatever additional actions it deems appropriate to effect such compliance,
including, without limitation, placing legends on share certificates and issuing
stop transfer notices to agents and registrars;

            (iii) Upon the exercise of all or a portion of an unvested Option
pursuant to Section 10(h), a Restricted Stock purchase agreement in a form
determined by the Administrator and signed by the Holder or other person then
entitled to exercise the Option or such portion of the Option; and

            (iv) In the event that the Option shall be exercised pursuant to
Section 10(f) by any person or persons other than the Holder, appropriate proof
of the right of such person or persons to exercise the Option.

        (c) CONDITIONS TO DELIVERY OF SHARE CERTIFICATES. The Company shall not
be required to issue or deliver any certificate or certificates for Shares
purchased upon the exercise of any Option or portion thereof prior to
fulfillment of all of the following conditions:

            (i) The admission of such Shares to listing on all stock exchanges
on which such class of stock is then listed;

            (ii) The completion of any registration or other qualification of
such Shares under any state or federal law, or under the rulings or regulations
of the Securities and Exchange Commission or any other governmental regulatory
body which the Administrator shall, in its absolute discretion, deem necessary
or advisable;

            (iii) The obtaining of any approval or other clearance from any
state or federal governmental agency which the Administrator shall, in its
absolute discretion, determine to be necessary or advisable;

            (iv) The lapse of such reasonable period of time following the
exercise of the Option as the Administrator may establish from time to time for
reasons of administrative convenience; and

            (v) The receipt by the Company of full payment for such Shares,
including payment of any applicable withholding tax, which in the discretion of
the Administrator may be in the form of consideration used by the Holder to pay
for such Shares under Section 9(b).

        (d) TERMINATION OF RELATIONSHIP AS A SERVICE PROVIDER. If a Holder
ceases to be a Service Provider other than by reason of the Holder's disability
or death, such Holder may exercise his or her Option within such period of time
as is specified in the Option Agreement to the extent that the Option is vested
on the date of termination (but in no event later than the expiration of the
term of the Option as set forth in the Option Agreement). In the absence of a


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specified time in the Option Agreement, the Option shall remain exercisable for
three (3) months following the Holder's termination. If, on the date of
termination, the Holder is not vested as to his or her entire Option, the Shares
covered by the unvested portion of the Option immediately cease to be issuable
under the Option and shall again become available for issuance under the Plan.
If, after termination, the Holder does not exercise his or her Option within the
time period specified herein, the Option shall terminate, and the Shares covered
by such Option shall again become available for issuance under the Plan.

        (e) DISABILITY OF HOLDER. If a Holder ceases to be a Service Provider as
a result of the Holder's disability, the Holder may exercise his or her Option
within such period of time as is specified in the Option Agreement to the extent
the Option is vested on the date of termination (but in no event later than the
expiration of the term of such Option as set forth in the Option Agreement). In
the absence of a specified time in the Option Agreement, the Option shall remain
exercisable for twelve (12) months following the Holder's termination. If such
disability is not a "disability" as such term is defined in Section 22(e)(3) of
the Code, in the case of an Incentive Stock Option such Incentive Stock Option
shall automatically cease to be treated as an Incentive Stock Option and shall
be treated for tax purposes as a Non-Qualified Stock Option from and after the
day which is three (3) months and one (1) day following such termination. If, on
the date of termination, the Holder is not vested as to his or her entire
Option, the Shares covered by the unvested portion of the Option shall
immediately cease to be issuable under the Option and shall again become
available for issuance under the Plan. If, after termination, the Holder does
not exercise his or her Option within the time specified herein, the Option
shall terminate, and the Shares covered by such Option shall again become
available for issuance under the Plan.

        (f) DEATH OF HOLDER. If a Holder dies while a Service Provider, the
Option may be exercised within such period of time as is specified in the Option
Agreement (but in no event later than the expiration of the term of such Option
as set forth in the Notice of Grant), by the Holder's estate or by a person who
acquires the right to exercise the Option by bequest or inheritance, but only to
the extent that the Option is vested on the date of death. In the absence of a
specified time in the Option Agreement, the Option shall remain exercisable for
twelve (12) months following the Holder's termination. If, at the time of death,
the Holder is not vested as to his or her entire Option, the Shares covered by
the unvested portion of the Option shall immediately cease to be issuable under
the Option and shall again become available for issuance under the Plan. The
Option may be exercised by the executor or administrator of the Holder's estate
or, if none, by the person(s) entitled to exercise the Option under the Holder's
will or the laws of descent or distribution. If the Option is not so exercised
within the time specified herein, the Option shall terminate, and the Shares
covered by such Option shall again become available for issuance under the Plan.

        (g) REGULATORY EXTENSION. A Holder's Option Agreement may provide that
if the exercise of the Option following the termination of the Holder's status
as a Service Provider (other than upon the Holder's death or Disability) would
be prohibited at any time solely because the issuance of shares would violate
the registration requirements under the Securities Act, then


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the Option shall terminate on the earlier of (i) the expiration of the term of
the Option set forth in Section 8 or (ii) the expiration of a period of three
(3) months after the termination of the Holder's status as a Service Provider
during which the exercise of the Option would not be in violation of such
registration requirements.

        (h) EARLY EXERCISABILITY. The Administrator may provide in the terms of
a Holder's Option Agreement that the Holder may, at any time before the Holder's
status as a Service Provider terminates, exercise the Option in whole or in part
prior to the full vesting of the Option; PROVIDED, HOWEVER, that subject to
Section 20, Shares acquired upon exercise of an Option which has not fully
vested may be subject to any forfeiture, transfer or other restrictions as the
Administrator may determine in its sole discretion.

        (i) BUYOUT PROVISIONS. The Administrator may at any time offer to buyout
for a payment in cash or Shares, an Option previously granted, based on such
terms and conditions as the Administrator shall establish and communicate to the
Holder at the time that such offer is made.

     11. NON-TRANSFERABILITY OF OPTIONS AND STOCK PURCHASE RIGHTS. Options and
Stock Purchase Rights may not be sold, pledged, assigned, hypothecated,
transferred, or disposed of in any manner other than by will or by the laws of
descent or distribution and may be exercised, during the lifetime of the Holder,
only by the Holder.

     12. STOCK PURCHASE RIGHTS.

        (a) RIGHTS TO PURCHASE. Stock Purchase Rights may be issued either
alone, in addition to, or in tandem with Options granted under the Plan and/or
cash awards made outside of the Plan. After the Administrator determines that it
will offer Stock Purchase Rights under the Plan, it shall advise the offeree in
writing of the terms, conditions and restrictions related to the offer,
including the number of Shares that such person shall be entitled to purchase,
the price to be paid, and the time within which such person must accept such
offer. The offer shall be accepted by execution of a Restricted Stock purchase
agreement in the form determined by the Administrator.

        (b) REPURCHASE RIGHT. Unless the Administrator determines otherwise, the
Restricted Stock purchase agreement shall grant the Company the right to
repurchase Shares acquired upon exercise of a Stock Purchase Right upon the
termination of the purchaser's status as a Service Provider for any reason.
Subject to Section 20, the purchase price for Shares repurchased by the Company
pursuant to such repurchase right and the rate at with such repurchase right
shall lapse shall be determined by the Administrator in its sole discretion, and
shall be set forth in the Restricted Stock purchase agreement.

        (c) OTHER PROVISIONS. The Restricted Stock purchase agreement shall
contain such other terms, provisions and conditions not inconsistent with the
Plan as may be determined by the Administrator in its sole discretion.


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        (d) RIGHTS AS A SHAREHOLDER. Once the Stock Purchase Right is exercised,
the purchaser shall have rights equivalent to those of a shareholder and shall
be a shareholder when his or her purchase is entered upon the records of the
duly authorized transfer agent of the Company. No adjustment shall be made for a
dividend or other right for which the record date is prior to the date the Stock
Purchase Right is exercised, except as provided in Section 13 of the Plan.

     13. ADJUSTMENTS UPON CHANGES IN CAPITALIZATION, MERGER OR ASSET SALE.

        (a) In the event that the Administrator determines that any dividend or
other distribution (whether in the form of cash, Common Stock, other securities,
or other property), recapitalization, reclassification, stock split, reverse
stock split, reorganization, merger, consolidation, split-up, spin-off,
combination, repurchase, liquidation, dissolution, or sale, transfer, exchange
or other disposition of all or substantially all of the assets of the Company,
or exchange of Common Stock or other securities of the Company, issuance of
warrants or other rights to purchase Common Stock or other securities of the
Company, or other similar corporate transaction or event, in the Administrator's
sole discretion, affects the Common Stock such that an adjustment is determined
by the Administrator to be appropriate in order to prevent dilution or
enlargement of the benefits or potential benefits intended to be made available
under the Plan or with respect to any Option, Stock Purchase Right or Restricted
Stock, then the Administrator shall, in such manner as it may deem equitable,
adjust any or all of:

            (i) The number and kind of shares of Common Stock (or other
securities or property) with respect to which Options or Stock Purchase Rights
may be granted or awarded (including, but not limited to, adjustments of the
limitations in Section 3 on the maximum number and kind of shares which may be
issued and adjustments of the maximum number of Shares that may be purchased by
any Holder in any calendar year pursuant to Section 6(c));

            (ii) The number and kind of shares of Common Stock (or other
securities or property) subject to outstanding Options, Stock Purchase Rights or
Restricted Stock; and

            (iii) The grant or exercise price with respect to any Option or
Stock Purchase Right.

        (b) In the event of any transaction or event described in Section 13(a),
the Administrator, in its sole and absolute discretion, and on such terms and
conditions as it deems appropriate, either by the terms of the Option, Stock
Purchase Right or Restricted Stock or by action taken prior to the occurrence of
such transaction or event and either automatically or upon the Holder's request,
is hereby authorized to take any one or more of the following actions whenever
the Administrator determines that such action is appropriate in order to prevent
dilution or enlargement of the benefits or potential benefits intended to be
made available under


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<Page>

the Plan or with respect to any Option, Stock Purchase Right or Restricted Stock
granted or issued under the Plan or to facilitate such transaction or event:

            (i) To provide for either the purchase of any such Option, Stock
Purchase Right or Restricted Stock for an amount of cash equal to the amount
that could have been obtained upon the exercise of such Option or Stock Purchase
Right or realization of the Holder's rights had such Option, Stock Purchase
Right or Restricted Stock been currently exercisable or payable or fully vested
or the replacement of such Option, Stock Purchase Right or Restricted Stock with
other rights or property selected by the Administrator in its sole discretion;

            (ii) To provide that such Option or Stock Purchase Right shall be
exercisable as to all shares covered thereby, notwithstanding anything to the
contrary in the Plan or the provisions of such Option or Stock Purchase Right;

            (iii) To provide that such Option, Stock Purchase Right or
Restricted Stock be assumed by the successor or survivor corporation, or a
parent or subsidiary thereof, or shall be substituted for by similar options,
rights or awards covering the stock of the successor or survivor corporation, or
a parent or subsidiary thereof, with appropriate adjustments as to the number
and kind of shares and prices;

            (iv) To make adjustments in the number and type of shares of Common
Stock (or other securities or property) subject to outstanding Options and Stock
Purchase Rights, and/or in the terms and conditions of (including the grant or
exercise price), and the criteria included in, outstanding Options, Stock
Purchase Rights or Restricted Stock or Options, Stock Purchase Rights or
Restricted Stock which may be granted in the future; and

            (v) To provide that immediately upon the consummation of such event,
such Option or Stock Purchase Right shall not be exercisable and shall
terminate; PROVIDED, that for a specified period of time prior to such event,
such Option or Stock Purchase Right shall be exercisable as to all Shares
covered thereby, and the restrictions imposed under an Option Agreement or
Restricted Stock purchase agreement upon some or all Shares may be terminated
and, in the case of Restricted Stock, some or all shares of such Restricted
Stock may cease to be subject to repurchase, notwithstanding anything to the
contrary in the Plan or the provisions of such Option, Stock Purchase Right or
Restricted Stock purchase agreement.

        (c) Subject to Section 3, the Administrator may, in its discretion,
include such further provisions and limitations in any Option, Stock Purchase
Right, Restricted Stock agreement or certificate, as it may deem equitable and
in the best interests of the Company.

        (d) If the Company undergoes an Acquisition, then any surviving
corporation or entity or acquiring corporation or entity, or affiliate of such
corporation or entity, may assume any Options, Stock Purchase Rights or
Restricted Stock outstanding under the Plan or may substitute similar stock
awards (including an award to acquire the same consideration paid to the


                                       13
<Page>

stockholders in the transaction described in this subsection 13(d)) for those
outstanding under the Plan. In the event any surviving corporation or entity or
acquiring corporation or entity in an Acquisition does not assume such Options,
Stock Purchase Rights or Restricted Stock or does not substitute similar stock
awards for those outstanding under the Plan, then with respect to (i) Options,
Stock Purchase Rights or Restricted Stock held by participants in the Plan whose
status as a Service Provider has not terminated prior to such event, the vesting
of such Options, Stock Purchase Rights or Restricted Stock (and, if applicable,
the time during which such awards may be exercised) shall be accelerated and
made fully exercisable and all restrictions thereon shall lapse at least ten
(10) days prior to the closing of the Acquisition (and the Options or Stock
Purchase Rights terminated if not exercised prior to the closing of such
Acquisition), and (ii) any other Options or Stock Purchase Rights outstanding
under the Plan, such Options or Stock Purchase rights shall be terminated if not
exercised prior to the closing of the Acquisition.

        (e) Notwithstanding the foregoing, in the event that the Company becomes
a party to a transaction that is intended to qualify for "pooling of interests"
accounting treatment and, but for one or more of the provisions of this Plan or
any Option Agreement or any Restricted Stock purchase agreement would so
qualify, then this Plan and any such agreement shall be interpreted so as to
preserve such accounting treatment, and to the extent that any provision of the
Plan or any such agreement would disqualify the transaction from pooling of
interests accounting treatment (including, if applicable, an entire Option
Agreement or Restricted Stock purchase agreement), then such provision shall be
null and void. All determinations to be made in connection with the preceding
sentence shall be made by the independent accounting firm whose opinion with
respect to "pooling of interests" treatment is required as a condition to the
Company's consummation of such transaction.

        (f) The existence of the Plan, any Option Agreement or Restricted Stock
purchase agreement and the Options or Stock Purchase Rights granted hereunder
shall not affect or restrict in any way the right or power of the Company or the
stockholders of the Company to make or authorize any adjustment,
recapitalization, reorganization or other change in the Company's capital
structure or its business, any merger or consolidation of the Company, any issue
of stock or of options, warrants or rights to purchase stock or of bonds,
debentures, preferred or prior preference stocks whose rights are superior to or
affect the Common Stock or the rights thereof or which are convertible into or
exchangeable for Common Stock, or the dissolution or liquidation of the Company,
or any sale or transfer of all or any part of its assets or business, or any
other corporate act or proceeding, whether of a similar character or otherwise.

     14. TIME OF GRANTING OPTIONS AND STOCK PURCHASE RIGHTS. The date of grant
of an Option or Stock Purchase Right shall, for all purposes, be the date on
which the Administrator makes the determination granting such Option or Stock
Purchase Right, or such other date as is determined by the Administrator. Notice
of the determination shall be given to each Employee or Consultant to whom an
Option or Stock Purchase Right is so granted within a reasonable time after the
date of such grant.

     15. AMENDMENT AND TERMINATION OF THE PLAN.


                                       14
<Page>

        (a) AMENDMENT AND TERMINATION. The Board may at any time wholly or
partially amend, alter, suspend or terminate the Plan. However, without approval
of the Company's stockholders given within twelve (12) months before or after
the action by the Board, no action of the Board may, except as provided in
Section 13, increase the limits imposed in Section 3 on the maximum number of
Shares which may be issued under the Plan or extend the term of the Plan under
Section 7.

        (b) STOCKHOLDER APPROVAL. The Board shall obtain stockholder approval of
any Plan amendment to the extent necessary and desirable to comply with
Applicable Laws.

        (c) EFFECT OF AMENDMENT OR TERMINATION. No amendment, alteration,
suspension or termination of the Plan shall impair the rights of any Holder,
unless mutually agreed otherwise between the Holder and the Administrator, which
agreement must be in writing and signed by the Holder and the Company.
Termination of the Plan shall not affect the Administrator's ability to exercise
the powers granted to it hereunder with respect to Options, Stock Purchase
Rights or Restricted Stock granted or awarded under the Plan prior to the date
of such termination.

     16. STOCKHOLDER APPROVAL. The Plan will be submitted for the approval of
the Company's stockholders within twelve (12) months after the date of the
Board's initial adoption of the Plan. Options, Stock Purchase Rights or
Restricted Stock may be granted or awarded prior to such stockholder approval,
provided that such Options, Stock Purchase Rights and Restricted Stock shall not
be exercisable, shall not vest and the restrictions thereon shall not lapse
prior to the time when the Plan is approved by the stockholders, and provided
further that if such approval has not been obtained at the end of said
twelve-month period, all Options, Stock Purchase Rights and Restricted Stock
previously granted or awarded under the Plan shall thereupon be canceled and
become null and void.

     17. INABILITY TO OBTAIN AUTHORITY. The inability of the Company to obtain
authority from any regulatory body having jurisdiction, which authority is
deemed by the Company's counsel to be necessary to the lawful issuance and sale
of any Shares hereunder, shall relieve the Company of any liability in respect
of the failure to issue or sell such Shares as to which such requisite authority
shall not have been obtained.

     18. RESERVATION OF SHARES. The Company, during the term of this Plan, shall
at all times reserve and keep available such number of Shares as shall be
sufficient to satisfy the requirements of the Plan.

     19. INFORMATION TO HOLDERS AND PURCHASERS. To the extent required by any
Applicable Laws, the Company shall provide to each Holder and to each individual
who acquires Shares pursuant to the Plan, not less frequently than annually
during the period such Holder or purchaser has one or more Options or Stock
Purchase Rights outstanding, and, in the case of an individual who acquires
Shares pursuant to the Plan, during the period such individual owns such Shares,
copies of annual financial statements. Notwithstanding the preceding sentence,
the Company


                                       15
<Page>

shall not be required to provide such statements to key employees whose duties
in connection with the Company assure their access to equivalent information.

     20. REPURCHASE PROVISIONS. The Administrator in its discretion may provide
that the Company may repurchase Shares acquired upon exercise of an Option or
Stock Purchase Right upon a Holder's termination as a Service Provider;
PROVIDED, that any such repurchase right shall be set forth in the applicable
Option Agreement or Restricted Stock purchase agreement or in another agreement
referred to in such agreement.

     21. INVESTMENT INTENT. The Company may require a Plan participant, as a
condition of exercising or acquiring stock under any Option or Stock Purchase
Right, (i) to give written assurances satisfactory to the Company as to the
participant's knowledge and experience in financial and business matters and/or
to employ a purchaser representative reasonably satisfactory to the Company who
is knowledgeable and experienced in financial and business matters and that he
or she is capable of evaluating, alone or together with the purchaser
representative, the merits and risks of exercising the Option or Stock Purchase
Right; and (ii) to give written assurances satisfactory to the Company stating
that the participant is acquiring the stock subject to the Option or Stock
Purchase Right for the participant's own account and not with any present
intention of selling or otherwise distributing the stock. The foregoing
requirements, and any assurances given pursuant to such requirements, shall be
inoperative if (A) the issuance of the shares upon the exercise or acquisition
of stock under the applicable Option or Stock Purchase Right has been registered
under a then currently effective registration statement under the Securities Act
or (B) as to any particular requirement, a determination is made by counsel for
the Company that such requirement need not be met in the circumstances under the
then applicable securities laws. The Company may, upon advice of counsel to the
Company, place legends on stock certificates issued under the Plan as such
counsel deems necessary or appropriate in order to comply with applicable
securities laws, including, but not limited to, legends restricting the transfer
of the stock.

     22. GOVERNING LAW. The validity and enforceability of this Plan shall be
governed by and construed in accordance with the laws of the State of Delaware
without regard to otherwise governing principles of conflicts of law.

     23. APPLICABILITY OF STOCKHOLDERS AGREEMENT. Upon receipt of any Option or
Stock Purchase Right, each participant under this Plan shall, automatically and
without further action on his or her part, (i) be deemed to be a party to, a
signatory of and bound by the Stockholders Agreement, dated March 14, 2001,
between the Company and the equity holders listed therein (the "Stockholders
Agreement").



                                  * * * * * * *



                                       16
<Page>


     I hereby certify that the Plan was duly adopted by the Stockholders of
Cogent Communications Group, Inc. on March 14, 2001.

     Executed in Washington, DC as of the 14th day of March 2001.


                                 /s/ DAVE SCHAEFFER
                                 ------------------------------------
                                 Dave Schaeffer
                                 President


                                  * * * * * * *

     I hereby certify that the Plan was duly adopted by the Board of Directors
of Cogent Communications Group, Inc. on March 7, 2001.

     Executed in Washington, DC as of the 14th day of March 2001.


                                 /s/ DAVE SCHAEFFER
                                 ------------------------------------
                                 Dave Schaeffer
                                 President


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