Does a US Patent help us with filing for patents in other countries?

The real question is how to manage time versus money and maximize the "bang for the buck" - in other words how to preserve maximum IP rights with limited start-up resources. There are several strategies that you may consider: (i) file only a PCT application and not the US to start with, this is a bit more expensive than US-only but preserves world-wide rights at least for some considerable time; (ii) file US now and PCT in 12 months, this will be less expensive now but in 12 months plan to spend more $$, or (iii) file a provisional US application now and then expand to PCT in 12 months. The last one is a least expensive way to proceed but you need a very comprehensive provisional specification to make it meaningful.

Filing in the U.S. alone will not help you and will not give you any protection overseas. If you are concerned about protection in other regions/countries, you should definitely evaluate your strategy. PCT coverage is wide and would give you extra time to consider where you want to file nationally, but is also more expensive than filing in the U.S. only, and will eventually require you to file nationally. Another option is to determine what countries/regions might be the early target markets for your IP and file only in those countries. Long-term, worldwide patent protection can be very expensive; therefore the most important item is to have an IP strategy in place before you make any decisions.

Not necessarily - each country determines patentability of an invention within its own jurisdiction. And even when one jurisdiction cites what it considers to be relevant prior art, which you may theoretically have to overcome in order to receive your patent, the patents cited are sometimes irrelevant. We recently received an international search report from WIPO in connection with our PCT application, however, the primary reference noted in the search report was entirely irrelevant to the present invention. Both a Canadian and US examiner cited that reference in their initial rejection, we noted to them why the reference was irrelevant, and both the Canadian and US applications as patents. So, again, what one jurisdiction may consider to be a relevant piece of prior art, it may not in fact be relevant, or another jurisdiction may cite other relevant prior art.