RFC 1464, "Using the Domain Name System To Store Arbitrary String Attributes", May 1993

Errata ID: 5193
Status: Verified
Type: Technical
Publication Format(s) : TEXT
Reported By: Victor Toni
Date Reported: 2017-12-02
Verifier Name: Warren Kumari (Ops AD)
Date Verified: 2017-12-06

Section 2. says:

string2      `abc`           string2=``abc``         "string2=``abc``"

It should say:

string2      `abc`           string2=`abc`         "string2=`abc`"

Notes:

Quote:
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Attribute Values

All printable ASCII characters are permitted in the attribute value.
No characters need to be quoted with a "`". In other words, the
first unquoted equals sign in the TXT record is the name/value
delimiter. All subsequent characters are part of the value.

Once again, note that in most implementations the backslash character
is an active quoting character (and must, itself, be quoted).

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"All subsequent characters are part of the value." would indicate that the part of the string after the "=" character could be copied as one.
The accent grave shoud not be escaped within the value.

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