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     EXHIBIT 10.13

SUMMARY OF SEVERANCE AGREEMENT WITH NAMED EXECUTIVE OFFICERS

Castelle has agreed to pay the Named Executive Officers (excluding Don Rich who
has a separate agreement) a severance payment ranging from three to six months
of their compensation, subject to standard payroll deductions and withholdings,
if the Company terminates the officer's employment without cause at any time or
if the Company terminates the officer's employment as a result of a change of
control. For purposes of the Company's agreement with the officers, "cause"
means misconduct, including: (i) conviction of any felony or a crime involving
moral turpitude; (ii) participation in a fraud or act of dishonesty against the
Company; (iii) willful breach of the Company's policies; (iv) intentional damage
to the Company's property; (v) material breach of the terms of the officer's
employment letter or the officer's Employee Proprietary Information and
Inventions Agreement; or (vi) conduct by the officer that, in the good faith and
reasonable determination of the Company, demonstrates gross unfitness to serve.
Physical or mental disability will not constitute cause.

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