Complex File Parsing Issue

Hello,

I have a file that looks like this:

Summary
A ABCD
A Category MarketValue Margin
A category1 1.0000000 1.000000
A category2 2.0000000 2.000000

H Totals Total Cash Net
H 2.00000 200000 2000000

Another Summary
B BCDE
B Activity MarketValue Margin
B activity1 3.00000 3.000000
B activity2 4.00000 4.000000

The items in blue are headers. I don't want to capture those. However, I want to capture all the data in black, and put it into 3 separate tables (or maybe the same table, under the appropriate column names)

This situation differs from anything I've done before in that you can't identify what row contains what data by what's in the row itself. That is, what's in the data rows is random and subject to change. So you can't search the row itself to determine which table it goes to.

However, if there's a way to capture all the rows after a certain header before the header changes again, that might work.

That is, get all rows between A Category MarketValue Margin and H Totals Total Cash Net
and
get all rows between H Totals Total Cash Net and Another Summary
and
get all rows after B Activity MarketValue Margin

Any examples of how I might script this?

Thanks