My text string is in cell D2:
Decision, ERC Case No. 2009-094 MC, In the Matter of the Application for Authority to Secure Loan from the National Electrification
Here are two solutions, one using the specific terms in the author's example, the other one expanding on the author's sample regex pattern which appears to match all ALLCAPS terms. I'm not sure which is wanted, so I gave both.
(Put the block of text in A1)
=regexreplace(regexreplace(REGEXREPLACE(A1,"\b\w[^A-Z]*\b","|"),"\W+","|"),"^\||\|$","")
Result:
ERC|MC|NEA|DIELCO
NB: The brunt of the work is in the CAPITALIZED formula, the lowercase functions are just for cleanup.
If you want space separation, the formula is a little simpler:
=trim(regexreplace(REGEXREPLACE(A1,"\b\w[^A-Z]*\b"," "),"\W+"," "))
Result:
ERC MC NEA DIELCO
(One way I like playing with regex in google spreadsheets is to read the regex pattern from another cell so I can change it without having to edit or re-paste into all the cells using that pattern. This looks so:
Cell A1:
Block of text
Cell B1 (no quote marks):
\b\w[^A-Z]*\b
Formula, in any cell:
=trim(regexreplace(REGEXREPLACE(A1,B$1," "),"\W+"," "))
By anchoring it to B$1, I can fill all my rows at once and the reference won't increment.)
Previous answer:
=regexreplace(join("|",IF(REGEXMATCH(A1,"ERC"),"ERC",""),IF(REGEXMATCH(A1,"DIELCO"),"DIELCO","")),"(^\||\|$)","")
Result:
ERC|DIELCO
As before, the brunt of the work is in the CAPITALIZED formula, the lowercase functions are just for cleanup.
This formula will find any ERC or DIELCO, or both in the block of text. The initial order doesn't matter, but the output will always be ERC followed by DIELCO (the order of appearance is lost). This fixes the shortcoming with the previous answer using "(bra).*(bra)" in that isolated ERC or DIELCO can still be matched.
This also has a simpler form with space separation:
=trim(join(" ",IF(REGEXMATCH(A1,"ERC"),"ERC",""),IF(REGEXMATCH(A1,"DIELCO"),"DIELCO","")))
Result:
ERC DIELCO