" What does it mean to ‘deduce title’?

During a residential conveyancing transaction, there is a requirement on the seller’s solicitors to deduce title. This occurs as an initial stage in the transaction, before exchange, and is forwarded to the purchaser’s solicitors."
https://www.ehlsolicitors.co.uk/what-does-it-mean-to-deduce-...

"conveyancing transaction

In order for the title of the property to be fully investigated by the purchaser’s solicitors, evidence of the title must be obtained by the seller’s solicitors and delivered to them. This process of delivering the evidence of title is known as deducing title, and the obligation varies between registered and unregistered land.

"Deducing Title To Unregistered Land

Under the Land Registration Act 2002 (which repealed the Land Registration Act 1925) it is compulsory for all land in England and Wales to be registered with the Land Registry. The trigger for registration is a change of ownership, such as a sale, gift or assent, or a mortgage or long lease. Once land is registered it will be added to the Land Registry's electronic register and this will be how the owner proves ownership. Until then, the paper title deeds are required.

Although the Land Registration Act 1925 introduced compulsory registration, it was not brought fully into force immediately. Different areas of the country became compulsory at different times and certain types of transaction, such as assents (a transfer to a beneficiary under a will) and mortgages were not caught. It wasn't until the 1990s that all areas and all transactions were subject to compulsory registration and as a result there is still a lot of unregistered land left.
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A Warning on DIY Conveyancing of Unregistered Land

The purpose of this guide is to explain how to carry out the conveyancing process when dealing with a sale of unregistered land, including deducing title, preparing an epitome, dealing with enquiries etc. Could a non-conveyancer use this guide to do his own conveyancing? In theory yes, but we would strongly advise against it."
http://freeconveyancingadvice.co.uk/sale-purchase/selling-un...