Legal Advise Please.... Newly surveyed Plot "Part-Owner" ask for Rental charge for the Demolished Structure for the Past 20 years.

Hi. I would like to have some legal advise please.. my mother got a summon letter from a baranggay concerning our neighboor asking us to pay a sum of Php480,000 ( 20,000 per year for a total of 20 years) for the backyard pen that was "been" built inside their plot ( the piggery "15-20 m2 area only" - and already demolished almost a year ago and since we havent use the facility for almost 5 years).. Their lot has no proper Lot measurement (until just recently they did a survey on the plot and claim that it was indeed inside their premises. In relation to this, they ask us to pay that heafty sum for settlement. my question is, Is this legal ? The "owners" who file a case againt us is not the title holder of the said lot , it was still named to their Great Grandfather's and to be subdivided to a lot of Heirs ( Them as one Family as a possible Heirs) We dont want to pay this large sum considering that they dont have claim before on that land and the Structure was already demolished? If we bring it until the Court, could we win the legal action they will made? We have the copy of the adjacent lot on which we base in good faith that we didnt construct the pen in their premises. Please help. I'm quite worried with my Parents since they are old already to think and worry like this things. thank you.

If your parents can prove that they believed in good faith they built the piggery on their own property and only accidentally encroached on that lot, then they are not required to pay anything, but if they knew the pen was not on their property then they are liable for indemnification to the owner.

Another Question.
Would it be possible for them to raised the case for my mom legally even if they are not the title Holder of the said land? We think it was still in the name on their Dead- Great Grand Fathers ( to be divided still to the Heirs) and them being the 3rd-4th Generation in the Family Tree....? Thank you in advance

if they can prove that they are the heirs, then it is possible.

I see.... Now they are asking for the settlement money ( as mentioned above) or else they will raise the legal case against us..... could we file as well a complaint? maybe extortion? they are now use of asking money for people they have grudge with ( they ask before for the settlement for 1 case as well ( i think sexual harrasment) , then drop the case when they got the money).

it is not extortion to threaten someone with legal action.