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b. 9-12

composition: (Op. 4), Sonata in C minor, Mvt IV

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The last C in bar 9 is an exceptionally clear example of the Chopinesque manner of writing notes on ledger lines, which consisted in providing the notehead with an additional vertical line pointing downwards, which could be considered a crotchet stem in some situations – see the Mazurka in B minor, Op. 24 No. 4, bar 23. E in bar 12 is also provided with such a line, shorter yet still distinct.

category imprint: Graphic ambiguousness; Source & stylistic information

issues: Uncertain notes on ledger lines

b. 10-12

composition: (Op. 4), Sonata in C minor, Mvt IV

Wedges & slurs from 2nd quaver in A, contextual interpretation

Whole-bar slurs in GE (→FE,EE,IE)

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The GE version (→FE,EE,IE), in which the wedges over the octaves at the beginning of bar 10 and 12 were ignored and the entire bars were encompassed with slurs, indicates that the engraver of GE was firmly convinced that Chopinesque slurs were generally careless. However, in this case, adjusting them to clear rhythmic structures certainly does not correspond to Chopin's intention, since in all further appearances of this phrase (bars 193-195 and 376-378) he wrote slurs running from the 2nd quaver in the bar.
It is only the ending of the slur in bar 10 that is to be considered inaccurate; when interpreted literally, in A it reaches only b.

category imprint: Differences between sources

issues: Inaccurate slurs in A , GE revisions

b. 10

composition: (Op. 4), Sonata in C minor, Mvt IV

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In A the last quaver was probably added later, while the irregular group marking was changed from 9 to 10.

category imprint: Corrections & alterations

issues: Corrections in A , Main-line changes

b. 11-12

composition: (Op. 4), Sonata in C minor, Mvt IV

in b. 11-12 & cresc. in A

 & cresc. in GE (→FE)

in EE

 in b. 12 & cresc. in IE

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The interpretation of the  hairpin in A, in spite of differing arms, seems quite simple – while writing the top arm, Chopin had to bypass the R.H. chord, hence we assume that it is the bottom arm that determines the intended length of the mark. In GE (→FE,EE) bar 12 opens a new line, which forced the division of the hairpin into two separate marks (it was one of the ways – in addition to the contemporary one – of reproducing hairpins in such situations). IE omitted the first one, probably due to the engraver's inattention.
In EE the cresc. indication in bar 12 was omitted, which could be a simplification of notation or an oversight.

category imprint: Graphic ambiguousness; Differences between sources

issues: EE revisions , Scope of dynamic hairpins , Errors in EE , GE revisions , Inaccuracies in A , Errors in IE

b. 11

composition: (Op. 4), Sonata in C minor, Mvt IV

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GE (→EE1,IE) has  before the highest note of the 2nd R.H. chord, which if read literally would give e2. The error probably occurred during proofreading – the  should have been added before the top note of the next chord. The mistake was corrected in FE and EE2.

category imprint: Interpretations within context; Differences between sources

issues: EE revisions , Errors in GE , FE revisions , Errors repeated in EE , Errors repeated in IE