Like many things, this is not so simple in practice. The meaning of 245$b depends on the preceding subfield (often, but not always $a). Preceded by : it's a subtitle. Preceded by = it's a parallel title. Preceded by ; it's a second title (another work) by the same person or people as the title in $a. In addition, you can have ISBD punctuation within the subfield for parallel titles or more titles by the same person/people.

From: Bibliographic Framework Transition Initiative Forum [[log in to unmask]] on behalf of Trail, Nate [[log in to unmask]]
Sent: Tuesday, January 29, 2013 6:59 AM
To: [log in to unmask]
Subject: Re: [BIBFRAME] Punctuation

If it's in a MARC record, there's no need to guess, because the subfields are already parsed parts. Title proper is 245$a, subtitle is 245$b, etc.

Nate Trail
Network Development and MARC  Standards Office
Technology Policy Mail stop 4402
Library Services
Library of Congress
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-----Original Message-----
From: J. McRee Elrod [mailto:[log in to unmask]]
Sent: Monday, January 28, 2013 5:22 PM
To: Trail, Nate
Cc: [log in to unmask]
Subject: Re: [BIBFRAME] Punctuation

>Maybe I'm missing something, but if we capture each subelement in it's
>own property, there'd be no need to parse a long string with ISBD
>punctuation.You'd know exactly what was in each, even if you didn't
>have a display system.

If it is in Chinese characters,  I don't know where the place ends and the publisher begins, nor where the title proper ends and subtitle begins.  I only got up the 300 characters and gave up.

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