BIM20270 - Trade: badges of trade: connection with existing trade
If there is an existing trade, then a similarity to the transaction under consideration may be a pointer to that transaction having a trading character.
In Harvey v Caulcott  33TC159 a builder claimed that certain properties that he had built and then sold many years later were investments and not part of his trading stock. On the facts of his case he succeeded but the court commented at page 165:
Such a case as the present is always coloured by the fact that the man is a builder. That no doubt puts a peculiar onus on him, to show that the profit from the sale of some property is profit from an investment, or profit from something which is not trading stock. That onus is not incapable of discharge.
The courts in other cases have also considered possible connections with a person's main trade. In CIR v Fraser  24TC498 (see BIM20230) the court commented at page 502:
It is in general more easy to hold that a single transaction entered into by an individual in the line of his own trade (although not part and parcel of his ordinary business) is an adventure in the nature of trade than to hold that a transaction entered into by an individual outside the line of his own trade or occupation is an adventure in the nature of trade.
More recently in Marson v Morton and Others  59TC381 the court posed the question, at page 391G:
Is the transaction in question in some way related to the trade which the taxpayer otherwise carries on? For example, a one-off purchase of silver cutlery by a general dealer is much more likely to be a trade transaction than such a purchase by a retired colonel.