You have all the same rights you had prior to the foreclosure; your lease is valid and enforceable. You shouldn't need to come to new terms, and the new owners have not only assumed all their obligations under the lease, but under the state Sanitary Code and other general landlord-tenant laws and regulations in Massachusetts.
What is your new landlord refusing to do? Is it a bank, other business entity, or a private person?
Assuming this was not a fraudulent lease, the owners are bound by it just as they would be bound if you were not related to the prior owner. If they will not honor the lease then you may be able to sue them for breach of contract.
You should talk to an attorney for help. We really need more details to answer.
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You may have rights under the Protecting Tenants at Foreclosure Act (PTFA). Once the new owner takes ownership, a 90 day notice needs to be served on all of the occupants. The notice requires the occupants to provide proof that they are bonafide tenants and not somehow related to the former owner who was foreclosed. If they are bonafide tenants and can prove this, then they are afforded the protections of the PTFA. They can remain in the premises under their lease, if there is a lease, unless the new owner intends to occupy the property as their primary residence (if, for instance, the property was sold to a 3rd party at auction rather than back to the lender). The 90-day notice period is required regardless of whether the occupant actually has a lease or was a tenant at will. It isn’t until the 90-day notice period expires that the new onwer can even serve the summary process/eviction complaint and then there is a timeframe under which you have to file it and then a hearing is scheduled. It sounds like you may not be completely protected by the federal statute if you are related to the former owner, but may benefit from some of the protections under state law. Here is a link to info on state law protections: http://www.mass.gov/ocabr/docs/foreclosure/tenants-rights.pdf . In any event, you may want to consult with a landlord/tenant attorney to ascertain your rights and obligations.
This "answer" is for information purposes only and is not intended as legal advice or to create an attorney-client relationship.
The new owners are stuck with you and your lease, whether they like it or not and they must give you notice of termination IAW Federal law (Protecting Tenants at Foreclosure Act) if they want you out. No new terms are required for your lease--now, if you had an oral lease agreement with your brother you may be in a bit of a bind in proving what those terms were.
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