I've recently registered a domain name, but was contacted by a big-name toy company recently, saying my domain name infringed on their trademark. The domain name does contain a toy's name (within the full domain name). They want me to transfer the domain name to them, but I want to keep it. What ramifications might there be?
Does the toy name has any meaning other than being a brand name? If not, then you are not safe. You are also in trouble if you were using the toy name for its derived meaning - for example "photoshoped" is a term of it's own nowadays, but using it still infringes on Adobe's trademark in some situations. It doesn't necessarilly matter whether you are dealing with toys or not, because using their trademark name in other contexts may have negative consequences for them. On the other hand, trademarks do have a scope attached to them, which may work in your favour.
If it means that much to them, they should have registered it already ;-)
Also, each registrar has a clear procedure to deal with these situations, which doesn't involve them sending you emails.
As someone else mentioned above, there is only likely an issue if you are selling toys or something related to toys (i.e. toy cleaning products or perhaps children's clothes).
Simple question to ask yourself, did I register the domain so people that buy product X from the toy company will come to my website to buy my product(s)/service(s)? If the answer is yes, they are likely correct.
You should certainly consult with an attorney though.
NOTE: My post is for informational purposes only and does not establish a lawyer/client relationship.