Exhibit 10.23

6-1162-IRS-0182

United Air Lines, Inc.

P. O. Box 66100

Chicago, IL 60601

 

Subject:    Priviledged and Confidential Matters Reference:    Purchase
Agreement No. 3427 (Purchase Agreement) between The Boeing Company (Boeing) and
United Air Lines, Inc. (Customer) relating to Model 787-8 aircraft (Aircraft)

This letter agreement (Letter Agreement) amends and supplements the Purchase
Agreement. All terms used but not defined in this Letter Agreement have the same
meaning as in the Purchase Agreement.

Boeing and Customer agree that certain commercial and financial information
contained in or transmitted pursuant to the Purchase Agreement and the Aircraft
General Terms Agreement (AGTA) (together the “Purchase Agreement”) between
Boeing and Customer and all letter agreements made a part of the Purchase
Agreement, including exhibits or attachments thereto are considered by Boeing
and Customer as privileged and confidential and the parties agree that the
information contained therein or transmitted pursuant to (Information)
represents confidential business information. Except as specified below, each of
Boeing and Customer is prohibited from disclosing the Information to any person,
entity, or government agency. Each party shall protect the confidentiality of
such Information in the manner similar to how a party protects its own
Information of a similar nature, but with no less than a reasonable standard of
care. This provision shall not restrict a party from taking any steps necessary
to protect and safeguard its interests relating to the Information, including
obtaining a protective order or other injunctive relief, where appropriate.

 

  (a) Employees. A party may disclose the Information to its own employees who
(i) have a need to know the Information for purposes of assisting said party in
the evaluation or administration of the Purchase Agreement or such party’s
business operations and (ii) have been instructed to not disclose the
Information except as provided by this Letter Agreement.

 

  (b)

Professional Advisors. A party may disclose the Information to its auditors,
insurers, financial advisors, consultants and attorneys (“Professional
Advisors”) who have a need to know the

 

P.A. No. 3427

Priviledged and Confidential Matters

BOEING / UNITED PROPRIETARY

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United Air Lines, Inc.

6-1162-IRS-0182

 

  Information in connection with providing services to said party only when said
party has first obtained from the Professional Advisor a written obligation of
confidentiality and restricted use that is no less restrictive than the terms of
this Letter Agreement. Each party shall be fully responsible to the other party
for the Professional Advisors’ compliance with such obligations.

 

  (c) Regulatory Requirements. A party may disclose in a regulatory or other
government filing that part of the Information which is required by applicable
law or regulation to be disclosed in such regulatory or other governmental
filings, including filings with the Securities and Exchange Commission (“SEC”),
but only in accordance with the following requirements:

 

  (i) The disclosing party shall advise the other party in writing of such
disclosure requirement prior to making such disclosure to enable the other party
to take those steps it deems necessary to protect the Information; and

 

  (ii) The disclosing party shall, as requested by the other party, seek
redaction and/or confidential treatment for the Information or parts thereof
from the SEC or other applicable regulators.

 

P.A. No. 3427

Priviledged and Confidential Matters

BOEING / UNITED PROPRIETARY

--------------------------------------------------------------------------------

United Air Lines, Inc.

6-1162-IRS-0182

 

Very truly yours, THE BOEING COMPANY By  

/s/ Nobuko Wiles

Its  

Attorney-In-Fact

ACCEPTED AND AGREED TO this Date: February 19, 2010 UNITED AIR LINES, INC.

By  

/s/ Kathryn A. Mikells

Its  

Executive Vice President and Chief Financial Officer

 

P.A. No. 3427

Priviledged and Confidential Matters

BOEING / UNITED PROPRIETARY