<P> A call for tenders was sent out requiring a deposit of $150,000 which would be lost if the tendered offer was withdrawn . Ron Engineering submitted an offer along with the required deposit in the form of a certified cheque . The submitted tenders were opened by the owner and Ron Engineering was the low bidder by a substantial margin . It was then discovered that the price on the tender documents was far lower than the price that Ron Engineering had intended to submit, and that they had made a mistake in calculating their total bid price . They informed the owner of the mistake and tried to have the offer changed . The change was refused, the contract was given to another company, and the owner kept Ron Engineering's bid deposit . Ron Engineering sued to get their deposit back . The owner counter-claimed for costs incurred as a result of having to go with a different bidder . At trial the counter-claim was dismissed but it was held that the owner was entitled to keep the deposit . The Ontario Court of Appeal reversed the trial decision and held, relying on the contractual doctrine of mistake, that Ron Engineering was entitled to get its deposit back . The owner appealed to the Supreme Court of Canada . </P> <P> The Supreme Court held that the tender process involved two contracts: </P> <Ul> <Li> Contract A - a unilateral contract arising automatically upon the submission of a tender, and </Li> <Li> Contract B - the contract awarded upon the tender's acceptance . </Li> </Ul> <Li> Contract A - a unilateral contract arising automatically upon the submission of a tender, and </Li>

Describe the ron engineering case and its significance