A couple of years back I designed a logo for a company. I was employed by my own company and was just starting out. As you can imagine I knew very little. Anyway desperate for work, when the company was approached by local company to create logo we agreed. I designed logo and it was invoiced simply as "design of logo" for which the company was paid £150. There was no talk of transfer of copyright and no documents were signed re this. No contract beyond "could you design us a logo" and a "yes" was made. These were an adjacent company of aquaintences. It was all rather casual. Thing is, now the logo is beginning to pop up everywhere and more importantly to me, they have begun to muck around with it and change it, which I resent. They trademarked their name and I am trying to see if this includes the logo. The company which this was done through and which I owned was dissolved by myself. Do I have any comeback re this. Have I any rights remaining over the design the main elements of which are unchanged? Or did I give over rights when I invoiced the £150 for "design of logo" Can I stop their manipulation of the logo.