Yes, your insurer can do this. The fact is that most long-term disability insurance companies require you to apply for Social Security disability in order to collect on your long-term benefits with them. This is because the insurance company can usually pay you much less (and sometimes maybe nothing at all) if you start getting Social Security disability. They will even offer to arrange for you to have a legal to file for you, although you always have the right to be represented by an attorney of your choice. The cost to you will almost always be the same whether you choose your own local attorney; typically no fee if you are turned down or a set percentage as determined by the Social Security Administration.