Thanks, but we need more details:

1) Boat A lee-bowed Boat B twice (i.e., tacked to leeward of B twice). For which of those leebow tacks is B claiming they were fouled?
2) Which (if any) of A's leebow tacks occurred within the zone (3 boatlengths for fleet racing, 2 for team and match racing)?
3) For each of A's leebow tacks, what was the gauge (sideway distance between boats) immediately after A completed her tack?
4) After each of A's leebow tacks, did B have to luff above close-hauled? If so, how much time elasped between A's tack and B's luff above close-hauled?
5) What was the sea state -- flat water, chop, swell?
6) How windy is it? What is the variability of the wind (puffiness)?
7) What kinds of boats are involved in this scenario? 
8) Did contact occur? Sounds like no, but double-checking. 

I'm not a judge, like many on this forum, but if I were sitting on a jury, these would be my initial questions.

Also, a diagram would be really useful.

A diagram would help (and man a mobile app boat scenario would be useful), but in a nutshell and in absence of other facts, it’s not likely.

On tack one (the lee bow), assuming B did not have to alter during A’s tack (RRS 13) or when A reached a close hauled course (RRS 15), A is in the clear. B must keep clear (RRS 11) from that point on.

On the next tack (both onto port), again, A is in the clear as long as she is keeping clear (RRS 11). 

On the last tack, B, while tacking is subject to RRS 13.  When A tacks she is also subject to RRS 13, and must keep clear of B, even if B is still tacking (RRS 13 last sentence). B, however is subject to RRS 16.1, limiting her altering such that she must allow A to alter course to keep clear.

Now like the first tack, A once again acquires right of way, so assuming B is able to keep clear once A gets to close hauled on starboard, A is in the clear. B then becomes give way (RRS 11).

Since A apparently tacked inside the zone, she’d normally be subject to RRS 18.3. However, that only applies to boats that have been on starboard since entering the zone, which it does not appear to be the case here. Thus, RRS 18.3 doesn’t apply here. Also, since A passed head to wind, any mark room rights she may have had turn off (RRS 18.2d). However, Part 2 section A and B still apply, and B is required to keep clear as noted above.

Tom .., nice touch (and well stated)

PS: the new US Sailng mobile app has a slightly awkward but usable basic boat scenario function. 

Thank you all for your comments. To answer the questions from Al above as best as I can recollect: 
1. Not sure when Boat B is claiming they were fouled, but spoke up when both boats were on starboard the second time, after rounding. 
2. The first lee bow was outside 3 boat lengths, the second one inside.
3. I can't be certain of the gauge, so I'm not going to guess. 
4. Boat A did not see Boat B luff up on either of the lee bows.
5. There was a light chop.
6. Winds were ~15 NNE, diminishing, so some puffiness/gusts
7. The boats are Marshall Sanderlings B cats, 18' single sail with a centerboard designed for shallow bay sailing. 
8. No contact occurred.

Tom, I really appreciate your analysis and will be digesting it (as I download the mobile app for future reference!)
Thanks!

In the first lee bow, both boats are outside the zone.  Rule 18.3 does not apply, A is subject to rule 13 after passing head to wind until she is on a close hauled course.  From the description, it appears there was no infringement.

At the second lee bow, when A passes head to wind, both she and B are on the same tack (starboard) and within the zone of the mark.  If both boats tacked to starboard inside the zone, then A is entitled to mark room from the moment she passes head to wind.  Even if A breaks rule 13, she will be exonerated as she is sailing within the mark room she is entitled to.
If B tacked to starboard outside the zone and A tacked inside the zone, rule 18.3 would apply.

Murray

Does this diagram describe the situation?
https://docs.google.com/presentation/d/1YE1HO8JWe6ulz2oXhVXxuBtjFHs3RCuPNTHAdITvaVo/edit?usp=sharing 
 

Tom, I think Murray's got it right.

Passing HTW only turns off 18.2(b-c) via 18.2(d).  18.2(a) remains after Boat A passes HTW (the focus of our recent thread).

Furthermore, before the last tack to starboard, if Boat A is inside and overlapped to windward of Boat B, def: mark-room provides Boat A "room to tack" because Boat A would be fetching the mark after she completes the tack. 

So this is how I see it breakdown .. 

Angelo, you and Murray are correct, 18.2a definitely applies. So, on the first leebow, no 18 as they’re outside the zone (per OP’s comments). On the tack to port, 18 would apply, and it would depend on whether A was overlapped with B as to whether A is entitled to room. On the last leebow, 18.2b and c get turned off by the tack, but A gets room per 18.2a.

This is what I get for writing at midnight!

In our area, the protest would be disallowed as too much time had passed. You have to say protest immediately. So B would have had to say protest just after he altered course. 

In response to Mike's diagram, it is not quite accurate as, both A and B remained on starboard (in the first instance) until well to the left of the mark. (Not sure if that makes a difference?) Some of the crew on boat A speculated that boat B was driving A off the course instead of sailing to the mark, (boat A believed B could lay it, hence the lee bow.) However, once on STBD, captain of Boat A said he could not head any higher and, as Boat B tends to foot anyway, perhaps they both sailed into a header(?) Hindsight says Boat A should have ducked B in the P/S encounter. 

I tried to draw it as I recollect, although disclaimer, I didn't check with either captain and at position 3, the boats were closer to the mark, but I didn't want to just show a jumble of triangles. Still a little amazed Boat A was able to lay it and not hit the mark.