Can property management put an advertisement sign for their business in the yard of the house I have leased?

I am renting a house in Indiana. The house is not a duplex or apartment complex. The problem that I have is that the property management company who manages the property has placed a permanent advertisement sign for their business 6 inches from my driveway. Now a lot of people think that my home is for rent, so I am constantly getting people knocking on my door, peeking through my windows, and traipsing through my yard. I pay almost $1,000 per month to lease this home, and I don't appreciate the intrusion and trespassing. I feel like I have leased the home, I take care of it and the yard, so I don't understand how they could advertise in my yard. They have refused to remove the advertisement sign. Is this legal? Thank you in advance for your help.