Attorneys from more than 45 law firms have joined to create the new Patent Trial and Appeal Board Bar Association, which launched Friday.Interim President Bob Steinberg, a partner at Latham & Watkins LLP in Washington, D.C., said it’s the first time a national bar association of this scale has been formed in 30 years.The U.S. Patent and Trademark Office’s Patent Trial and Appeal Board (PTAB) has seen a significant increase in patent-validity challenges since the America Invents Act was signed in 2011. When …