Is it illegal not to inform the taxman

tsb

I'm in dispute over a business I have, with a family member. The business have been running for over 10 years and I've run it single handed, on a self employed bases. The business is all above board and I've paid all the taxes due over the years. All of a sudden this family member has stated that they are a partner in this business and is expecting there to be a big pot of cash in a bank account, for their half of the profits.
Solicitors are now involved, but they are a waste of time.
The situation is complicated but my question is- If the family member was a partner,was it illegal for them, not to inform the taxman, that they had a interest in a business and can you tell me where it states that is illegal. This might help my case

olivetti

I cannot see they have a leg to stand on unless there is some kind of formal partnership agreement that the pair of you signed. Do they have a legitimate claim to being a partner, is there such an agreement and what involvement did they have in running the business? Did they put in any capital or extract anything out of the business?

sandiep

The Inland Revenue require you to register for self employment within 3 months of starting up. They can/will charge interest and penalties on all back tax, and the longer it has been going the harder the line they'll take.

I am not sure that it is illegal, but they will definiately be penalised, and require to immediately stump up all and any tax and NI.