What impact could the patents applied for by Craight Wright have on Bitcoin development if granted? What impact will this have if all the patents he applied for are granted. Could it create liability for Bitcoin developers who attempt to use some of his patented ideas when making future pull requests?

"Since February, Wright has filed more than 50 patent applications in Britain through Antigua-registered EITC Holdings Ltd, which a source close to the company confirmed was connected to Wright, government records show."

"Nearly all the British filings involve the term "blockchain" or its more generic description, the "distributed ledger". The patent approval process typically takes several year"
Searching the http://patents.stackexchange.com site, I found a question that linked here:

http://ask.metafilter.com/216885/What-happens-if-an-opensource-app-intentionally-violates-a-software-patent#3129948


  An open source program can infringe a patent just the same as a
  commercial one. There is no requirement that the infringement be for
  profit, since infringement may consist of making, using, selling,
  offering to sell, or importing the invention. 35 U.S.C. § 271.
  Infringement may be direct (i.e. the author making the software) or
  indirect (e.g. the author distributing it to others intending that
  they use it in an infringing manner). 
  
  What's more, by copying a program knowing that it likely infringes a
  patent, the open source author may be liable for willful patent
  infringement. That carries with it the possibility of treble damages
  and an award of attorney's fees and costs. 35 U.S.C. § 284.


So yes, it appears as though Bitcoin developers could be held liable.

The article also continues to state that it is often not financially feasible for patent holders to go after open source software, since software is global but patents vary country to country.  Also, there are not necessarily assets to be won from open source developers.

Personally, I feel that Craig Wright has been applying for patents not to target Bitcoin, but the growing blockchain industry.  The banks and financial institutions adopting blockchain solutions do have assets that can be easily won (or settled) with patent suits.

DISCLAIMER: I am not a lawyer, and am way out of my element with this answer :)