( i) In calculating damages for the DC services portion of the
Subcontract, did the trial judge err by failing to apply the
Open Window Bakery minimum performance principle?
( ii) If he did, and DC services damages should have been calculated in accordance with the formula contained in the Subcontract’s termination for convenience clause, did the trial
judge err in interpreting that clause?
( iii) In calculating damages for the AMS services portion of the
Subcontract, did the trial judge err in his interpretation of
the Subcontract’s limitation of liability clause?
( iv) Finally, if the trial judge erred in any part of his calculation
of damages, should his award of costs be set aside and
the issue of the costs below be remitted to him for further
III. First Issue: Does the Open Window Bakery Principle Apply to
the Calculation of Damages for Data Conversion Services?
A. The issue stated
The Subcontract’s termination provisions
 Article 17 of the Subcontract afforded Sapient two rights
to terminate. First, s. 17.2 entitled Sapient to terminate the
entire Subcontract for cause by providing notice to Siemens in
certain circumstances, one of which (contained in s. 17.2.2)
was where Siemens “commits a material breach of its obligations
under this Agreement and such breach is not capable of being
 A more limited termination right was available in s. 17.4
of the Subcontract: it entitled Sapient to terminate the DC services part of the Subcontract “for convenience”.
 Sapient relied on the s. 17.2 termination “for cause” provision in its June 29, 2009 termination letter by which it terminated the entire Subcontract “effective immediately”.
 When Sapient terminated the Subcontract, the DC services
were “almost, if not entirely, complete”: trial reasons (“reasons”),
at para. 325. There was little work left for Sapient to finish.
 At the time of termination, Siemens was putting in place
the organization to provide AMS services, but those services
would not commence until the “go-live” date in September 2009.
The trial judge found Sapient “had no intention of terminating
just the Data Conversion portion of the Subcontract”: reasons,
para. 331. Sapient wanted to provide the AMS services itself.
And, in the result, the day after it terminated Siemens, Sapient