Development deals are often exchanged or completed under extreme time pressure. Documentation may even be dealt with by email, with hard copies to follow. But in the urgency to do the deal, can you be sure that the other party's documentation was properly executed? And what are the consequences if not?

It is relatively unusual for the execution of a document to be challenged, but two recent cases serve as a warning not to ignore this issue.

The first is the case of Re Armstrong Brands Ltd (in Administration) [2015] EWHC 3303 (Ch.). In June 2008 the company arranged funding, to be secured by a debenture. At some point thereafter, Keiron Armstrong, the sole director of the company (together with the company secretary) signed the debenture. However, it was not dated and completed until September 2008 by which time Mr Armstrong was no longer a director.

So had it been properly executed? In 2014 the funder appointed administrators, who sought a declaration as to the validity of their appointment - which turned upon the answer to this question. The answer was not clear cut. However, the High Court held there was enough supporting evidence to decide (on a balance of probabilities) that the debenture had been signed when Mr Armstrong was still a director. That meant it had been validly executed, even though it had been dated and completed after he left office. It was, therefore, enforceable by the funder.

The same applies on sales particularly residential sales to joint purchasers. In Marlbray Ltd v Laditi and another [2016] EWCA Civ 476, Dr Laditi had signed a contract (purportedly on behalf of himself and his wife) to buy a hotel room unit in an aparthotel development. He subsequently claimed that the sale contract was unenforceable. One of his arguments was that his wife had not authorised him to sign on her behalf. The Court of Appeal accepted that argument.

However, the contract contained a provision that the named purchasers were jointly and severally liable. In light of that clause, the Court held that the contract was in any event enforceable against Dr Laditi, albeit not against his wife.

These cases are a timely reminder to check the validity of execution prior to exchange or completion.