This is quite unusual - it's usual for the employment contract for a developer to include a clause dictating whatever you create in the course of your employment is owned by your company but as far as what you do outside the course of your employment - this is pretty odd.
You should check what your contract says, but regardless of what it says, if you aren't using your company's source code, equipment and designs etc I think this would be hard to enforce (without knowing the facts here). Even if you did sign an employment contract including this, if you are not developing anything that builds on top of your company's work, this could be seen as restriction of your trade (or a similar concept) and be unenforceable but whether this is the case or not is really depends on the specific facts here.
I think your best bet is to take a look at your contract and if it does include wording to the effect that whatever you develop (whether this be in work or not) then you should talk to an IP lawyer who has some experience with employment issues like this.
By way of my background - I'm an ex corporate M&A lawyer based in London so IP/employment isn't my specialist area and it can be quite tricky so I would recommend you try and find one to make sure you get this right.
I should also add that I'm currently building a UK based platform to help people with legal issues find good lawyers at fair prices which will be launched in the next month, but if you need assistance before this get in touch and maybe I can help find the right lawyer for you (this will be free to you - charges are deducted from the lawyer).
You should check what your contract says, but regardless of what it says, if you aren't using your company's source code, equipment and designs etc I think this would be hard to enforce (without knowing the facts here). Even if you did sign an employment contract including this, if you are not developing anything that builds on top of your company's work, this could be seen as restriction of your trade (or a similar concept) and be unenforceable but whether this is the case or not is really depends on the specific facts here.
I think your best bet is to take a look at your contract and if it does include wording to the effect that whatever you develop (whether this be in work or not) then you should talk to an IP lawyer who has some experience with employment issues like this.
By way of my background - I'm an ex corporate M&A lawyer based in London so IP/employment isn't my specialist area and it can be quite tricky so I would recommend you try and find one to make sure you get this right.
I should also add that I'm currently building a UK based platform to help people with legal issues find good lawyers at fair prices which will be launched in the next month, but if you need assistance before this get in touch and maybe I can help find the right lawyer for you (this will be free to you - charges are deducted from the lawyer).