Do I need to change my company name?

As others have indicated, you should certainly consult a trademark attorney promptly. However, their ability to force you to change your name is...

You would certainly have common law rights to the trademark based on your use. Whoever told you that registration is unnecessary gave you bad...

If I have a tagline that I want no one else to be able to use, is that consider copyrighting or trademarking?

Short phrases are generally not subject to copyright protection. If you intend to use the tagline to identify your business as a source of a...

What are the implications of registering a trademark for a mobile application when an application with the same name exists?

If you know that someone has pre-existing rights to a trademark, then you cannot truthfully sign the application to register the trademark. If you...

What are the legalities behind selling products that have been posted online as a DIY project?

Without knowing exactly what was posted on Pinterest, what businesses or other activities the entities who posted the items to Pinterest might be...

Can I duplicate a product and make my own changes without infringing?

Although there is a reasonably good possibility that you can, the only way to be certain is to check for any utility patent, design patent, trade...

Is it legal to publish a book or website with images of current celebrity lookalikes?

It depends on multiple factors. You would need to be concerned with copyright to the images as well as publicity rights of the individuals...

Could I use copyrighted/trademarked logos in a digital graphic design portfolio piece?

I would hesitate to use real company logos, since this could be seen as implying sponsorship, affiliation, or endorsement by those companies. You...

Can I trademark a name previously used with my business partner ?

As others noted, the partnership likely has a common law right the trademark, and your use outside the partnership could be a problem not only from...

I make high quality ink pens of all types and colors

You would need to negotiate a license agreement with the Steelers in order to avoid trademark infringement. Given that you are only selling a...