Exhibit 10.1

Execution Copy

DIGITAL REALTY TRUST, L.P.

4.125% Exchangeable Senior Debentures Due 2026

Registration Rights Agreement

New York, New York

August 15, 2006

Citigroup Global Markets Inc.

MERRILL LYNCH & CO.

Merrill Lynch, Pierce, Fenner & Smith Incorporated

As Representatives of the Initial Purchasers

c/o Citigroup Global Markets Inc.

388 Greenwich Street

New York, New York 10013

Ladies and Gentlemen:

Digital Realty Trust, L.P., a limited partnership organized under the laws of
the State of Maryland (the “Operating Partnership”), proposes to issue and sell
to certain purchasers (the “Initial Purchasers”), for whom you (the
“Representatives”) are acting as representatives, its 4.125% Exchangeable Senior
Debentures Due 2026 (the “Debentures”), upon the terms set forth in the Purchase
Agreement by and among the Operating Partnership, Digital Realty Trust, Inc., a
corporation organized under the laws of the State of Maryland (the “Company”),
and the Representatives, dated August 9, 2006 (the “Purchase Agreement”),
relating to the initial placement (the “Initial Placement”) of the Debentures.
In certain circumstances, the Debentures will be exchangeable into shares of
common stock, $0.01 par value (the “Common Stock”), of the Company. The
Debentures will be fully and unconditionally guaranteed as to the payment of
principal and interest by the Company. To induce the Initial Purchasers to enter
into the Purchase Agreement and to satisfy obligations thereunder, the holders
of the Debentures will have the benefit of this registration rights agreement by
and among the Operating Partnership, the Company and the Initial Purchasers
whereby the Company agrees with you for your benefit and the benefit of the
holders from time to time of the Debentures (including the Initial Purchasers)
(each a “Holder” and, collectively, the “Holders”), as follows:

1. Definitions. Capitalized terms used herein without definition shall have
their respective meanings set forth in the Purchase Agreement. As used in this
Agreement, the following capitalized defined terms shall have the following
meanings:

“Act” shall mean the Securities Act of 1933, as amended, and the rules and
regulations of the Commission promulgated thereunder.

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“Affiliate” shall have the meaning specified in Rule 405 under the Act and the
terms “controlling” and “controlled” shall have meanings correlative thereto.

“Automatic Shelf Registration Statement” shall mean a Registration Statement
filed by a Well-Known Seasoned Issuer which shall become effective upon filing
thereof pursuant to General Instruction I.D for Form S-3.

“Broker-Dealer” shall mean any broker or dealer registered as such under the
Exchange Act.

“Business Day” shall mean any day other than a Saturday, a Sunday or a legal
holiday or a day on which banking institutions or trust companies are authorized
or obligated by law to close in New York City.

“Closing Date” shall mean the date of the first issuance of the Debentures.

“Commission” shall mean the Securities and Exchange Commission.

“Debenture” shall have the meaning set forth in the preamble.

“Deferral Period” shall have the meaning indicated in Section 3(i) hereof.

“Exchange Act” shall mean the Securities Exchange Act of 1934, as amended, and
the rules and regulations of the Commission promulgated thereunder.

“Exchange Price” shall have the meaning specified in the Indenture.

“Final Memorandum” shall mean the offering memorandum, dated August 9, 2006,
relating to the Debentures, including any and all annexes thereto and any
information incorporated by reference therein as of such date.

“Holder” shall have the meaning set forth in the preamble hereto.

“Indenture” shall mean the Indenture relating to the Debentures, dated as of
August 15, 2006, by and among the Operating Partnership, the Company, as
guarantor, and Wells Fargo Bank, N.A., as trustee, as the same may be amended
from time to time in accordance with the terms thereof.

“Initial Placement” shall have the meaning set forth in the preamble hereto.

“Initial Purchasers” shall have the meaning set forth in the preamble hereto.

“Losses” shall have the meaning set forth in Section 5(d) hereof.

“Majority Holders” shall mean, on any date, Holders of a majority of the Common
Stock registered under the Shelf Registration Statement.

 

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“Managing Underwriters” shall mean the investment banker or investment bankers
and manager or managers that administer an underwritten offering, if any,
conducted pursuant to Section 6 hereof.

“NASD Rules” shall mean the Conduct Rules and the By-Laws of the National
Association of Securities Dealers, Inc.

“Notice and Questionnaire” shall mean a written notice delivered to the Company
substantially in the form attached as Annex A to the Final Memorandum.

“Notice Holder” shall mean, on any date, any Holder of Registrable Securities
that has delivered a Notice and Questionnaire to the Company on or prior to such
date.

“Prospectus” shall mean a prospectus included in the Shelf Registration
Statement (including, without limitation, a prospectus that discloses
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule 430A or Rule 430B under the Act),
as amended or supplemented by any prospectus supplement, with respect to the
terms of the offering of any portion of the Common Stock covered by the Shelf
Registration Statement, and all amendments and supplements thereto, including
any and all exhibits thereto and any information incorporated by reference
therein.

“Purchase Agreement” shall have the meaning set forth in the preamble hereto.

“Registrable Securities” shall mean shares of Common Stock initially issuable in
exchange for the Debentures initially sold to the Initial Purchasers pursuant to
the Purchase Agreement other than those that have (i) been registered under the
Shelf Registration Statement and disposed of in accordance therewith, (ii) have
become eligible to be sold without restriction as contemplated by Rule 144(k)
under the Act or any successor rule or regulation thereto that may be adopted by
the Commission and (iii) ceased to be outstanding.

“Registration Default Damages” shall have the meaning set forth in Section 7
hereof.

“Shelf Registration Period” shall have the meaning set forth in Section 2(c)
hereof.

“Shelf Registration Statement” shall mean a “shelf” registration statement of
the Company pursuant to the provisions of Section 2 hereof which covers some or
all of the Common Stock on an appropriate form under Rule 415 under the Act, or
any similar rule that may be adopted by the Commission, amendments and
supplements to such registration statement, including post-effective amendments,
in each case including the Prospectus contained therein, all exhibits thereto
and all material incorporated by reference therein.

“underwriter” shall mean any underwriter of Common Stock in connection with an
offering thereof under the Shelf Registration Statement.

“Well-Known Seasoned Issuer” shall have the meaning set forth in Rule 405 under
the Act.

 

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2. Shelf Registration. (a) The Company shall as promptly as practicable (but in
no event more than 270 days after the Closing Date) file with the Commission a
Shelf Registration Statement (which shall be, if the Company is then a WKSI, an
Automatic Shelf Registration Statement) providing for the registration of, and
the sale on a continuous or delayed basis by the Holders of, all of the
Registrable Securities, from time to time in accordance with the methods of
distribution elected by such Holders, pursuant to Rule 415 under the Act or any
similar rule that may be adopted by the Commission.

(b) If the Shelf Registration Statement is not an Automatic Shelf Registration
Statement, the Company shall use its reasonable efforts to cause the Shelf
Registration Statement to become or be declared effective under the Act no later
than 270 days after the Closing Date.

(c) The Company shall use its reasonable efforts to keep the Shelf Registration
Statement continuously effective, supplemented and amended as required by the
Act, in order to permit the Prospectus forming part thereof to be usable by
Holders for a period (the “Shelf Registration Period”) from the date the Shelf
Registration Statement is declared effective by the Commission (or becomes
effective in the case of an Automatic Shelf Registration Statement) until the
earlier of (i) the 20th trading day immediately following the maturity date of
the Debentures or (ii) the date upon which there are no Debentures or
Registrable Securities outstanding. The Company shall be deemed not to have used
its reasonable efforts to keep the Shelf Registration Statement effective during
the Shelf Registration Period if it voluntarily takes any action that would
result in Holders of Registrable Securities not being able to offer and sell
such Common Stock at any time during the Shelf Registration Period, unless such
action is (x) required by applicable law or otherwise undertaken by the Company
in good faith and for valid business reasons (not including avoidance of the
Company’s obligations hereunder), including the acquisition or divestiture of
assets, and (y) permitted by Section 3(i) hereof. None of the Company, the
Operating Partnership or any of their respective securityholders (other than
Holders of Registrable Securities) shall have the right to include any
securities of the Company or the Operating Partnership in any Shelf Registration
Statement other than Registrable Securities.

(d) The Company shall cause the Shelf Registration Statement and the related
Prospectus and any amendment or supplement thereto, as of the effective date of
the Shelf Registration Statement or such amendment or supplement, (i) to comply
in all material respects with the applicable requirements of the Act; and
(ii) not to contain any untrue statement of a material fact or omit to state a
material fact required to be stated therein or necessary in order to make the
statements therein (in the case of the Prospectus, in the light of the
circumstances under which they were made) not misleading.

(e) The Company shall issue a press release through a reputable national
newswire service announcing the anticipated effective date of the Shelf
Registration Statement at least 15 Business Days prior to the anticipated
effective date thereof. Each Holder of Registrable Securities agrees to deliver
a Notice and Questionnaire and such other information as the Company may
reasonably request in writing, if any, to the Company at least ten Business Days
prior to the anticipated effective date of the Shelf Registration Statement as
announced in the press release. From and after the effective date of the Shelf
Registration Statement, the Company shall use reasonable efforts, as promptly as
is practicable after the date a Notice and

 

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Questionnaire is delivered, and in any event within 20 Business Days after such
date, (i) if required by applicable law, to file with the Commission a
post-effective amendment to the Shelf Registration Statement; provided, that the
Company shall not be required to file more than one post-effective amendment in
any 90-day period in accordance with this Section 2(e)(i) or to prepare and, if
permitted or required by applicable law, to file a supplement to the related
Prospectus or an amendment or supplement to any document incorporated therein by
reference or file any other required document so that the Holder delivering such
Notice and Questionnaire is named as a selling securityholder in the Shelf
Registration Statement and the related Prospectus, and so that such Holder is
permitted to deliver such Prospectus to purchasers of the Registrable Securities
in accordance with applicable law and, if the Company shall file a
post-effective amendment to the Shelf Registration Statement, use reasonable
efforts to cause such post-effective amendment to be declared effective under
the Act as promptly as is practicable; (ii) provide such Holder, upon request,
copies of any documents filed pursuant to Section 2(e)(i) hereof; and
(iii) notify such Holder as promptly as practicable after the effectiveness
under the Act of any post-effective amendment filed pursuant to Section 2(e)(i)
hereof; provided, that if such Notice and Questionnaire is delivered during a
Deferral Period, the Company shall so inform the Holder delivering such Notice
and Questionnaire and shall take the actions set forth in clauses (i), (ii) and
(iii) above upon expiration of the Deferral Period in accordance with
Section 3(i) hereof. Notwithstanding anything contained herein to the contrary,
the Company shall be under no obligation to name any Holder that is not a Notice
Holder as a selling securityholder in the Shelf Registration Statement or
related Prospectus; provided, however, that any Holder that becomes a Notice
Holder pursuant to the provisions of this Section 2(e) (whether or not such
Holder was a Notice Holder at the effective date of the Shelf Registration
Statement) shall be named as a selling securityholder in the Shelf Registration
Statement or related Prospectus in accordance with the requirements of this
Section 2(e). Notwithstanding the foregoing, if (A) the Debentures are called
for redemption and the then prevailing market price of the Common Stock is above
the Exchange Price or (B) the Debentures are exchanged as provided for in
Section 13.01(i), 13.01(ii) or 13.01(iv) of the Indenture, then the Company
shall use reasonable efforts to file the post-effective amendment or supplement
within five Business Days of the redemption date or the end of the exchange
period, as applicable.

3. Registration Procedures. The following provisions shall apply in connection
with the Shelf Registration Statement.

(a) The Company shall:

(i) furnish to each of the Representatives and to counsel for the Notice
Holders, not less than five Business Days prior to the filing thereof with the
Commission, a copy of the Shelf Registration Statement and each amendment
thereto and each amendment or supplement, if any, to the Prospectus included
therein (including all documents incorporated by reference therein after the
initial filing) and shall use its reasonable efforts to reflect in each such
document, when so filed with the Commission, such comments as the
Representatives reasonably propose; and

(ii) include information regarding the Notice Holders and the methods of
distribution they have elected for their Registrable Securities provided to the

 

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Company in Notices and Questionnaires as necessary to permit such distribution
by the methods specified therein.

(b) The Company shall ensure that:

(i) the Shelf Registration Statement and any amendment thereto and any
Prospectus forming part thereof and any amendment or supplement thereto complies
in all material respects with the Act; and

(ii) the Shelf Registration Statement and any amendment thereto does not, when
it becomes effective, contain an untrue statement of a material fact or omit to
state a material fact required to be stated therein or necessary to make the
statements therein not misleading.

(c) The Company shall advise the Representatives, the Notice Holders and any
underwriter that has provided in writing to the Company a telephone or facsimile
number and address for notices, and confirm such advice in writing, if requested
(which notice pursuant to clauses (ii)-(v) hereof shall be accompanied by an
instruction to suspend the use of the Prospectus until the Company shall have
remedied the basis for such suspension):

(i) when the Shelf Registration Statement and any amendment thereto has been
filed with the Commission and when the Shelf Registration Statement or any
post-effective amendment thereto has become effective;

(ii) of any request by the Commission for any amendment or supplement to the
Shelf Registration Statement or the Prospectus or for additional information;

(iii) of the issuance by the Commission of any stop order suspending the
effectiveness of the Shelf Registration Statement or the institution or
threatening of any proceeding for that purpose;

(iv) of the receipt by the Company of any notification with respect to the
suspension of the qualification of the Common Stock included therein for sale in
any jurisdiction or the institution or threatening of any proceeding for such
purpose; and

(v) of the happening of any event that requires any change in the Shelf
Registration Statement or the Prospectus so that, as of such date, they (A) do
not contain any untrue statement of a material fact and (B) do not omit to state
a material fact required to be stated therein or necessary to make the
statements therein (in the case of the Prospectus, in the light of the
circumstances under which they were made) not misleading.

(d) The Company shall use its reasonable efforts to prevent the issuance of any
order suspending the effectiveness of the Shelf Registration Statement or the
qualification of the securities therein for sale in any jurisdiction and, if
issued, to obtain as soon as possible the withdrawal thereof. The Company shall
undertake additional reasonable actions as required to

 

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permit unrestricted resales of the Common Stock in accordance with the terms and
conditions of this Agreement.

(e) Upon request, the Company shall furnish to each Notice Holder, without
charge, at least one copy of the Shelf Registration Statement and any
post-effective amendment thereto, including all material incorporated therein by
reference, and, if a Notice Holder so requests in writing, all exhibits thereto
(including exhibits incorporated by reference therein).

(f) During the Shelf Registration Period, the Company shall promptly deliver to
each Initial Purchaser, each Notice Holder, and any sales or placement agents or
underwriters acting on their behalf, without charge, as many copies of the
Prospectus (including the preliminary Prospectus, if any) included in the Shelf
Registration Statement and any amendment or supplement thereto as any such
person may reasonably request. The Company consents to the use of the Prospectus
or any amendment or supplement thereto by each of the foregoing in connection
with the offering and sale of the Common Stock.

(g) Prior to any offering of Common Stock pursuant to the Shelf Registration
Statement, the Company shall arrange for the qualification of the Common Stock
for sale under the laws of such jurisdictions as any Notice Holder shall
reasonably request and shall maintain such qualification in effect so long as
required; provided that in no event shall the Company be obligated to qualify to
do business in any jurisdiction where it is not then so qualified or to take any
action that would subject it to service of process in suits, other than those
arising out of the Initial Placement or any offering pursuant to the Shelf
Registration Statement, in any jurisdiction where it is not then so subject.

(h) Upon the occurrence of any event contemplated by subsections (c)(ii) through
(v) above, the Company shall promptly (or within the time period provided for by
Section 3(i) hereof, if applicable) prepare a post-effective amendment to the
Shelf Registration Statement or an amendment or supplement to the related
Prospectus or file any other required document so that, as thereafter delivered
to Initial Purchasers of the securities included therein, the Prospectus will
not include an untrue statement of a material fact or omit to state any material
fact required to be stated therein or necessary to make the statements therein,
in the light of the circumstances under which they were made, not misleading.

(i) Upon the occurrence or existence of any pending corporate development,
public filings with the Commission or any other material event that, in the
reasonable judgment of the Company, makes it appropriate to suspend the
availability of the Shelf Registration Statement and the related Prospectus, the
Company shall give notice (without notice of the nature or details of such
events) to the Notice Holders that the availability of the Shelf Registration
Statement is suspended and, upon actual receipt of any such notice, each Notice
Holder agrees not to sell any Registrable Securities pursuant to the Shelf
Registration Statement until such Notice Holder’s receipt of copies of the
supplemented or amended Prospectus provided for in Section 3(i) hereof, or until
it is advised in writing by the Company that the Prospectus may be used, and has
received copies of any additional or supplemental filings that are incorporated
or deemed incorporated by reference in such Prospectus. The period during which
the availability of the Shelf Registration Statement and any Prospectus is
suspended (the “Deferral Period”) shall not exceed 45 days in any 90-day period
or 90 days in any 360-day

 

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period; provided, that, if the event triggering the Deferral Period relates to a
proposed or pending material business transaction, the disclosure of which the
board of directors of the Company determines in good faith would be reasonably
likely to impede the ability to consummate the transaction or would otherwise be
seriously detrimental to the Company and its subsidiaries taken a whole, the
Company may extend the Deferral Period from 45 days to 60 days in any 90-day
period or from 90 days to 120 days in any 360-day period.

(j) The Company shall comply with all applicable rules and regulations of the
Commission and shall make generally available to its securityholders an earnings
statement satisfying the provisions of Section 11(a) of the Act as soon as
practicable after the effective date of the Shelf Registration Statement and in
any event no later than 45 days after the end of a 12-month period (or 90 days,
if such period is a fiscal year) beginning with the first month of the Company’s
first fiscal quarter commencing after the effective date of the Shelf
Registration Statement.

(k) The Company may require each Holder of Common Stock to be sold pursuant to
the Shelf Registration Statement to furnish to the Company such information
regarding the Holder and the distribution of such Common Stock as the Company
may from time to time reasonably require for inclusion in the Shelf Registration
Statement. The Company may exclude from the Shelf Registration Statement the
Common Stock of any Holder that unreasonably fails to furnish such information
within a reasonable time after receiving such request.

(l) Subject to Section 6 hereof, the Company shall enter into customary
agreements (including, if requested, an underwriting agreement in customary
form) and take all other appropriate actions in order to expedite or facilitate
the registration or the disposition of the Common Stock, and in connection
therewith, if an underwriting agreement is entered into, cause the same to
contain customary indemnification provisions and procedures.

(m) Subject to Section 6 hereof, the Company shall:

(i) make reasonably available for inspection by the Holders of Common Stock to
be registered thereunder, any underwriter participating in any disposition
pursuant to the Shelf Registration Statement, and any attorney, accountant or
other agent retained by the Holders or any such underwriter all relevant
financial and other records and pertinent corporate documents of the Company and
its subsidiaries;

(ii) cause the Company’s officers, directors, employees, accountants and
auditors to supply all relevant information reasonably requested by the Holders
or any such underwriter, attorney, accountant or agent in connection with the
Shelf Registration Statement as is customary for similar due diligence
examinations;

(iii) make such representations and warranties to the Holders of Common Stock
registered thereunder and the underwriters, if any, in form, substance and scope
as are customarily made by issuers to underwriters in

 

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primary underwritten offerings and covering matters including, but not limited
to, those set forth in the Purchase Agreement;

(iv) obtain opinions of counsel to the Company and updates thereof (which
counsel and opinions (in form, scope and substance) shall be reasonably
satisfactory to the Managing Underwriters, if any) addressed to each selling
Holder and the underwriters, if any, covering such matters as are customarily
covered in opinions requested in underwritten offerings and such other matters
as may be reasonably requested by such Holders and underwriters;

(v) obtain “comfort” letters and updates thereof from the independent certified
public accountants of the Company (and, if necessary, any other independent
certified public accountants of any subsidiary of the Company or of any business
acquired by the Company for which financial statements and financial data are,
or are required to be, included in the Shelf Registration Statement), addressed
to each selling Holder of Common Stock registered thereunder and the
underwriters, if any, in customary form and covering matters of the type
customarily covered in “comfort” letters in connection with primary underwritten
offerings; and

(vi) deliver such documents and certificates as may be reasonably requested by
the Majority Holders or the Managing Underwriters, if any, including those to
evidence compliance with Section 3(i) hereof and with any customary conditions
contained in the underwriting agreement or other agreement entered into by the
Company.

The actions set forth in clauses (iii), (iv), (v) and (vi) of this paragraph
(m) shall be performed in connection with any underwriting or similar agreement
as and to the extent required thereunder.

(n) In the event that any Broker-Dealer shall underwrite any Common Stock or
participate as a member of an underwriting syndicate or selling group or “assist
in the distribution” (within the meaning of the NASD Rules) thereof, whether as
a Holder of such Common Stock or as an underwriter, a placement or sales agent
or a broker or dealer in respect thereof, or otherwise, the Company shall assist
such Broker-Dealer in complying with the NASD Rules.

(o) The Company shall use its reasonable efforts to take all other steps
necessary to effect the registration of the Common Stock covered by the Shelf
Registration Statement.

4. Registration Expenses. The Company shall bear all expenses incurred in
connection with the performance of its obligations under Sections 2 and 3 hereof
and shall reimburse the Holders for the reasonable fees and disbursements of one
firm or counsel (which shall initially be Goodwin Procter LLP, but which may be
another nationally recognized law firm experienced in securities matters
designated by the Majority Holders) to act as counsel for the Holders in
connection therewith.

 

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5. Indemnification and Contribution. (a) The Company and the Operating
Partnership agree to indemnify and hold harmless each Holder of Common Stock
covered by the Shelf Registration Statement, each Initial Purchaser, the
directors, officers, employees, Affiliates and agents of each such Holder or
Initial Purchaser and each person who controls any such Holder or Initial
Purchaser within the meaning of either the Act or the Exchange Act against any
and all losses, claims, damages or liabilities, joint or several, to which they
or any of them may become subject under the Act, the Exchange Act or other
federal or state statutory law or regulation, at common law or otherwise,
insofar as such losses, claims, damages or liabilities (or actions in respect
thereof) arise out of or are based upon any untrue statement or alleged untrue
statement of a material fact contained in the Shelf Registration Statement as
originally filed or in any amendment thereof, or in any preliminary Prospectus
or the Prospectus, or in any amendment thereof or supplement thereto, or arise
out of or are based upon the omission or alleged omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein (in the case of any preliminary Prospectus or the Prospectus, in the
light of the circumstances under which they were made) not misleading, and
agrees to reimburse each such indemnified party, as incurred, for any legal or
other expenses reasonably incurred by it in connection with investigating or
defending any such loss, claim, damage, liability or action; provided, however,
that the Company and the Operating Partnership will not be liable in any such
case to the extent that any such loss, claim, damage or liability arises out of
or is based upon any such untrue statement or alleged untrue statement or
omission or alleged omission made therein in reliance upon and in conformity
with written information furnished to the Company by or on behalf of the party
claiming indemnification specifically for inclusion therein. This indemnity
agreement shall be in addition to any liability that the Company and the
Operating Partnership may otherwise have.

The Company and the Operating Partnership also agree to indemnify as provided in
this Section 5(a) or contribute as provided in Section 5(d) hereof to Losses of
each underwriter, if any, of Common Stock registered under the Shelf
Registration Statement, its directors, officers, employees, Affiliates or agents
and each person who controls such underwriter on substantially the same basis as
that of the indemnification of the Initial Purchasers and the selling Holders
provided in this paragraph (a) and shall, if requested by any Holder, enter into
an underwriting agreement reflecting such agreement, as provided in Section 3(l)
hereof.

(b) Each Holder of securities covered by the Shelf Registration Statement
(including each Initial Purchaser that is a Holder, in such capacity) severally
and not jointly agrees to indemnify and hold harmless the Company and the
Operating Partnership, each of its directors, each of its officers who signs the
Shelf Registration Statement and each person who controls the Company or the
Operating Partnership within the meaning of either the Act or the Exchange Act,
to the same extent as the foregoing indemnity from the Company and the Operating
Partnership to each such Holder, but only with reference to written information
relating to such Holder furnished to the Company by or on behalf of such Holder
specifically for inclusion in the documents referred to in the foregoing
indemnity. This indemnity agreement shall be acknowledged by each Notice Holder
that is not an Initial Purchaser in such Notice Holder’s Notice and
Questionnaire and shall be in addition to any liability that any such Notice
Holder may otherwise have.

 

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(c) Promptly after receipt by an indemnified party under this Section 5 or
notice of the commencement of any action, such indemnified party will, if a
claim in respect thereof is to be made against the indemnifying party under this
Section 5, notify the indemnifying party in writing of the commencement thereof;
but the failure so to notify the indemnifying party (i) will not relieve it from
liability under paragraph (a) or (b) above unless and to the extent it did not
otherwise learn of such action and such failure results in the forfeiture by the
indemnifying party of substantial rights and defenses; and (ii) will not, in any
event, relieve the indemnifying party from any obligations to any indemnified
party other than the indemnification obligation provided in paragraph (a) or
(b) above. The indemnifying party shall be entitled to appoint counsel
(including local counsel) of the indemnifying party’s choice at the indemnifying
party’s expense to represent the indemnified party in any action for which
indemnification is sought (in which case the indemnifying party shall not
thereafter be responsible for the fees and expenses of any separate counsel,
other than local counsel if not appointed by the indemnifying party, retained by
the indemnified party or parties except as set forth below); provided, however,
that such counsel shall be satisfactory to the indemnified party.
Notwithstanding the indemnifying party’s election to appoint counsel (including
local counsel) to represent the indemnified party in an action, the indemnified
party shall have the right to employ separate counsel (including local counsel),
and the indemnifying party shall bear the reasonable fees, costs and expenses of
such separate counsel if (i) the use of counsel chosen by the indemnifying party
to represent the indemnified party would present such counsel with a conflict of
interest; (ii) the actual or potential defendants in, or targets of, any such
action include both the indemnified party and the indemnifying party and the
indemnified party shall have reasonably concluded that there may be legal
defenses available to it and/or other indemnified parties that are different
from or additional to those available to the indemnifying party; (iii) the
indemnifying party shall not have employed counsel satisfactory to the
indemnified party to represent the indemnified party within a reasonable time
after notice of the institution of such action; or (iv) the indemnifying party
shall authorize the indemnified party to employ separate counsel at the expense
of the indemnifying party. An indemnifying party will not, without the prior
written consent of the indemnified parties, settle or compromise or consent to
the entry of any judgment with respect to any pending or threatened claim,
action, suit or proceeding in respect of which indemnification or contribution
may be sought hereunder (whether or not the indemnified parties are actual or
potential parties to such claim or action) unless such settlement, compromise or
consent includes an unconditional release of each indemnified party from all
liability arising out of such claim, action, suit or proceeding.

(d) In the event that the indemnity provided in paragraph (a) or (b) of this
Section 5 is unavailable to or insufficient to hold harmless an indemnified
party for any reason, then each applicable indemnifying party shall have a joint
and several obligation to contribute to the aggregate losses, claims, damages
and liabilities (including legal or other expenses reasonably incurred in
connection with investigating or defending loss, claim, liability, damage or
action) (collectively “Losses”) to which such indemnified party may be subject
in such proportion as is appropriate to reflect the relative benefits received
by such indemnifying party, on the one hand, and such indemnified party, on the
other hand, from the Initial Placement and the Shelf Registration Statement
which resulted in such Losses; provided, however, that in no case shall any
Initial Purchaser be responsible, in the aggregate, for any amount in excess of
the purchase discount or commission applicable to the Debentures, as set forth
in the Final Memorandum, nor shall any underwriter be responsible for any amount
in excess of the

 

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underwriting discount or commission applicable to the securities purchased by
such underwriter under the Shelf Registration Statement which resulted in such
Losses. If the allocation provided by the immediately preceding sentence is
unavailable for any reason, the indemnifying party and the indemnified party
shall contribute in such proportion as is appropriate to reflect not only such
relative benefits but also the relative fault of such indemnifying party, on the
one hand, and such indemnified party, on the other hand, in connection with the
statements or omissions which resulted in such Losses as well as any other
relevant equitable considerations. Benefits received by the Company and the
Operating Partnership shall be deemed to be equal to the total net proceeds from
the Initial Placement (before deducting expenses) as set forth in the Final
Memorandum. Benefits received by the Initial Purchasers shall be deemed to be
equal to the total purchase discounts and commissions as set forth on the cover
page of the Final Memorandum, and benefits received by any other Holders shall
be deemed to be equal to the value of receiving Common Stock registered under
the Act. Benefits received by any underwriter shall be deemed to be equal to the
total underwriting discounts and commissions, as set forth on the cover page of
the Prospectus forming a part of the Shelf Registration Statement which resulted
in such Losses. Relative fault shall be determined by reference to, among other
things, whether any untrue or any alleged untrue statement of a material fact or
omission or alleged omission to state a material fact relates to information
provided by the indemnifying party, on the one hand, or by the indemnified
party, on the other hand, the intent of the parties and their relative
knowledge, access to information and opportunity to correct or prevent such
untrue statement or omission. The parties agree that it would not be just and
equitable if contribution were determined by pro rata allocation (even if the
Holders were treated as one entity for such purpose) or any other method of
allocation which does not take account of the equitable considerations referred
to above. Notwithstanding the provisions of this paragraph (d), no person guilty
of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act)
shall be entitled to contribution from any person who was not guilty of such
fraudulent misrepresentation. For purposes of this Section 5, each person who
controls a Holder within the meaning of either the Act or the Exchange Act and
each director, officer, employee and agent of such Holder shall have the same
rights to contribution as such Holder, and each person who controls the Company
or the Operating Partnership within the meaning of either the Act or the
Exchange Act, each officer of the Company or the Operating Partnership who shall
have signed the Shelf Registration Statement and each director of the Company or
the Operating Partnership shall have the same rights to contribution as the
Company and the Operating Partnership, subject in each case to the applicable
terms and conditions of this paragraph (d).

(e) The provisions of this Section 5 shall remain in full force and effect,
regardless of any investigation made by or on behalf of any Holder or the
Company or the Operating Partnership or any of the indemnified persons referred
to in this Section 5, and shall survive the sale by a Holder of securities
covered by the Shelf Registration Statement.

6. Underwritten Registrations. (a) In no event will the method of distribution
of Registrable Securities take the form of an underwritten offering without the
prior written consent of the Company.

(b) If any shares of Common Stock covered by the Shelf Registration Statement
are to be sold in an underwritten offering, the Managing Underwriters shall be

 

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selected by the Company, subject to the prior written consent of the Majority
Holders, which consent shall not be unreasonably withheld.

(c) No person may participate in any underwritten offering pursuant to the Shelf
Registration Statement unless such person (i) agrees to sell such person’s
shares of Common Stock on the basis reasonably provided in any underwriting
arrangements approved by the persons entitled hereunder to approve such
arrangements; and (ii) completes and executes all questionnaires, powers of
attorney, indemnities, underwriting agreements and other documents reasonably
required under the terms of such underwriting arrangements.

7. Registration Defaults. If any of the following events shall occur, then the
Company shall pay liquidated damages (the “Registration Default Damages”) to the
Holders as follows:

(a) if the Shelf Registration Statement (which shall be, if the Company is then
a WKSI, an Automatic Shelf Registration Statement) is not filed with the
Commission on or prior to the 270th day following the Closing Date, then
commencing on the 271st day after the Closing Date, Registration Default Damages
shall accrue on the aggregate outstanding principal amount of the Debentures, at
a rate of 0.25% per annum for the first 90 days from and including such 271st
day and 0.50% per annum thereafter; or

(b) if the Shelf Registration Statement is not declared effective by the
Commission (or has not become effective in the case of an Automatic Shelf
Registration Statement) on or prior to the 270th day following the Closing Date,
then commencing on the 271st day after the Closing Date, Registration Default
Damages shall accrue on the aggregate outstanding principal amount of the
Debentures, at a rate of 0.25% per annum for the first 90 days from and
including such 271st day and 0.50% per annum thereafter; or

(c) if the Shelf Registration Statement has been declared or become effective
but ceases to be effective or usable for the offer and sale of the Registrable
Securities, other than in connection with (A) a Deferral Period or (B) as a
result of a requirement to file a post-effective amendment or supplement to the
Prospectus to make changes to the information regarding selling securityholders
or the plan of distribution provided for therein, at any time during the Shelf
Registration Period and the Company does not cure the lapse of effectiveness or
usability within ten Business Days (or, if a Deferral Period is then in effect
and subject to the 20 Business Day filing requirement and the proviso regarding
the filing of post-effective amendments in Section 2(e) with respect to any
Notice and Questionnaire received during such period, within ten Business Days
following the expiration of such Deferral Period or period permitted pursuant to
Section 2(e)) then Registration Default Damages shall accrue on the aggregate
outstanding principal amount of the Debentures at a rate of 0.25% per annum for
the first 90 days from and including the day following such tenth Business Day
and 0.50% per annum thereafter; or

(d) if the Company through its omission fails to name as a selling
securityholder any Holder that had complied timely with its obligations
hereunder in a manner to entitle such Holder to be so named in (i) the Shelf
Registration Statement at the time it first became effective or (ii) any
Prospectus at the later of time of filing thereof or the time the Shelf

 

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Registration Statement of which the Prospectus forms a part becomes effective
then Registration Default Damages shall accrue, on the aggregate outstanding
principal amount of the Debentures held by such Holder, at a rate of 0.25% per
annum for the first 90 days from and including the day following the effective
date of such Shelf Registration Statement or the time of filing of such
Prospectus, as the case may be, and 0.50% per annum thereafter; or

(e) if the aggregate duration of Deferral Periods in any period exceeds the
number of days permitted in respect of such period pursuant to Section 3(i)
hereof, then commencing on the day the aggregate duration of Deferral Periods in
any period exceeds the number of days permitted in respect of such period,
Registration Default Damages shall accrue on the aggregate outstanding principal
amount of the Debentures at a rate of 0.25% per annum for the first 90 days from
and including such date, and 0.50% per annum thereafter;

provided, however, that (1) upon the filing of the Shelf Registration Statement
(in the case of paragraph (a) above), (2) upon the effectiveness of the Shelf
Registration Statement (in the case of paragraph (b) above), (3) upon such time
as the Shelf Registration Statement which had ceased to remain effective or
usable for resales again becomes effective and usable for resales (in the case
of paragraph (c) above), (4) upon the time such Holder is permitted to sell its
Registrable Securities pursuant to any Shelf Registration Statement and
Prospectus in accordance with applicable law (in the case of paragraph
(d) above) or (5) upon the termination of the Deferral Period that caused the
limit on the aggregate duration of Deferral Periods in a period set forth in
Section 3(i) to be exceeded (in the case of paragraph (f) above), the
Registration Default Damages shall cease to accrue.

Any amounts of Registration Default Damages due pursuant to this Section 7 will
be payable in cash on the next succeeding interest payment date to Holders
entitled to receive such Registration Default Damages on the relevant record
dates for the payment of interest. If any Debenture ceases to be outstanding
during any period for which Registration Default Damages are accruing, the
Company will prorate the Registration Default Damages payable with respect to
such Debenture.

The Registration Default Damages rate on the Debentures shall not exceed in the
aggregate 0.50% per annum and shall not be payable under more than one clause
above for any given period of time, except that if Registration Default Damages
would be payable because of more than one Registration Default, but at a rate of
0.25% per annum under one Registration Default and at a rate of 0.50% per annum
under the other, then the Registration Default Damages rate shall be the higher
rate of 0.50% per annum.

Notwithstanding any provision in this Agreement, in no event shall Registration
Default Damages accrue to holders of Common Shares issued upon exchange of
Debentures. In lieu thereof, the Company shall increase the Conversion Rate (as
defined in the Indenture) by 3% for each $1,000 principal amount of Debentures
exchanged at a time when such Registration Default has occurred and is
continuing.

8. No Inconsistent Agreements. Neither the Company nor the Operating Partnership
has entered into, and each agrees not to enter into, any agreement with respect
to its securities that is inconsistent with the registration rights granted to
the Holders herein.

 

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9. Rule 144A and Rule 144. So long as any Registrable Securities remain
outstanding, the Company shall use its reasonable best efforts to file the
reports required to be filed by it under Rule 144A(d)(4) under the Act and the
Exchange Act in a timely manner and, if at anytime the Company is not required
to file such reports, it will, upon the written request of any Holder of
Registrable Securities, make publicly available other information so long as
necessary to permit sales of such Holder’s Registrable Securities pursuant to
Rules 144 and 144A of the Act. The Company covenants that it will take such
further action as any Holder of Registrable Securities may reasonably request,
all to the extent required from time to time to enable such Holder to sell
Registrable Securities without registration under the Act within the limitation
of the exemptions provided by Rules 144 and 144A (including, without limitation,
the requirements of Rule 144A(d)(4)). Upon the written request of any Holder of
Registrable Securities, the Company shall deliver to such Holder a written
statement as to whether it has complied with such requirements. Notwithstanding
the foregoing, nothing in this Section 9 shall be deemed to require the Company
or the Operating Partnership to register any of its securities pursuant to the
Exchange Act.

10. Listing. The Company shall use its reasonable efforts to maintain the
approval of the Common Share for listing on the New York Stock Exchange.

11. Amendments and Waivers. The provisions of this Agreement may not be amended,
qualified, modified or supplemented, and waivers or consents to departures from
the provisions hereof may not be given, unless the Company has obtained the
written consent of the Majority Holders; provided that, with respect to any
matter that directly or indirectly affects the rights of any Initial Purchaser
hereunder, the Company shall obtain the written consent of each such Initial
Purchaser against which such amendment, qualification, supplement, waiver or
consent is to be effective; provided, further, that no amendment, qualification,
supplement, waiver or consent with respect to Section 7 hereof shall be
effective as against any Holder of Registrable Securities unless consented to in
writing by such Holder; and provided, further, that the provisions of this
Article 11 may not be amended, qualified, modified or supplemented, and waivers
or consents to departures from the provisions hereof may not be given, unless
the Company has obtained the written consent of the Initial Purchasers and each
Holder.

12. Notices. All notices and other communications provided for or permitted
hereunder shall be made in writing by hand-delivery, first-class mail, telex,
telecopier or air courier guaranteeing overnight delivery:

(a) if to a Holder, at the most current address given by such holder to the
Company in accordance with the provisions of the Notice and Questionnaire;

(b) if to the Initial Purchasers or the Representatives, initially at the
address or addresses set forth in the Purchase Agreement; and

(c) if to the Company or the Operating Partnership, initially at its address set
forth in the Purchase Agreement.

All such notices and communications shall be deemed to have been duly given when
received.

 

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The Initial Purchasers, the Company or the Operating Partnership by notice to
the other parties may designate additional or different addresses for subsequent
notices or communications.

Notwithstanding the foregoing, notices given to Holders holding Debentures in
book-entry form may be given through the facilities of DTC or any successor
depository.

13. Remedies. Each Holder, in addition to being entitled to exercise all rights
provided to it herein or in the Purchase Agreement or granted by law, including
recovery of liquidated or other damages, will be entitled to specific
performance of its rights under this Agreement. The Company and the Operating
Partnership agree that monetary damages would not be adequate compensation for
any loss incurred by reason of a breach by them of the provisions of this
Agreement and hereby agree to waive in any action for specific performance the
defense that a remedy at law would be adequate.

14. Successors. This Agreement shall inure to the benefit of and be binding upon
the parties hereto, their respective successors and assigns, including, without
the need for an express assignment or any consent by the Company or the
Operating Partnership thereto, subsequent Holders of Common Stock, and the
indemnified persons referred to in Section 5 hereof. The Company and the
Operating Partnership hereby agree to extend the benefits of this Agreement to
any Holder of Common Stock, and any such Holder may specifically enforce the
provisions of this Agreement as if an original party hereto.

15. Counterparts. This Agreement may be signed in one or more counterparts, each
of which shall constitute an original and all of which together shall constitute
one and the same agreement.

16. Headings. The section headings used herein are for convenience only and
shall not affect the construction hereof.

17. Applicable Law. This Agreement shall be governed by and construed in
accordance with the laws of the State of New York applicable to contracts made
and to be performed in the State of New York. The parties hereto each hereby
waive any right to trial by jury in any action, proceeding or counterclaim
arising out of or relating to this Agreement.

18. Severability. In the event that any one of more of the provisions contained
herein, or the application thereof in any circumstances, is held invalid,
illegal or unenforceable in any respect for any reason, the validity, legality
and enforceability of any such provision in every other respect and of the
remaining provisions hereof shall not be in any way impaired or affected
thereby, it being intended that all of the rights and privileges of the parties
shall be enforceable to the fullest extent permitted by law.

19. Common Stock Held by the Company, etc. Whenever the consent or approval of
Holders of a specified percentage of principal amount of Common Stock is
required hereunder, Common Stock held by the Company or its Affiliates (other
than subsequent Holders of Common Stock if such subsequent Holders are deemed to
be Affiliates solely by reason of their holdings of such Common Stock) shall not
be counted in determining whether such consent or approval was given by the
Holders of such required percentage.

 

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If the foregoing is in accordance with your understanding of our agreement,
please sign and return to us the enclosed duplicate hereof, whereupon this
letter and your acceptance shall represent a binding agreement by and among the
Company, the Operating Partnership and the several Initial Purchasers.

 

Very truly yours, Digital Realty Trust, Inc. By:   /s/ Michael F. Foust  

Name:

  Michael F. Foust  

Title:

  Chief Executive Officer Digital Realty Trust, L.P. By:  

Digital Realty Trust, Inc.,

its General Partner

By:   /s/ Michael F. Foust  

Name:

  Michael F. Foust  

Title:

  Chief Executive Officer

The foregoing Agreement is hereby confirmed and accepted as of the date first
above written.

Citigroup Global Markets Inc.

MERRILL LYNCH & CO.

Merrill Lynch, Pierce, Fenner & Smith Incorporated

By: Citigroup Global Markets Inc.

 

By:   /s/ David Kieske   Name:   David Kieske   Title:   Vice President

For itself and the other several Initial Purchasers named in Schedule I to the
Purchase Agreement

 

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