Copyright © Kevin Stone

R9C3 can only be <1>

R3C8 is the only square in row 3 that can be <6>

R4C2 is the only square in row 4 that can be <7>

R3C1 is the only square in row 3 that can be <7>

R1C9 is the only square in row 1 that can be <7>

R6C8 is the only square in row 6 that can be <8>

R6C4 is the only square in row 6 that can be <2>

R6C5 is the only square in row 6 that can be <5>

R9C2 is the only square in row 9 that can be <5>

R8C2 can only be <9>

R8C3 can only be <2>

R7C2 can only be <3>

R6C2 can only be <4>

R9C1 can only be <6>

R6C3 can only be <9>

R6C1 can only be <3>

R3C3 can only be <4>

R5C1 can only be <1>

R2C1 can only be <2>

R1C1 can only be <9>

R3C6 is the only square in row 3 that can be <2>

R8C4 is the only square in row 8 that can be <5>

R7C7 is the only square in row 7 that can be <5>

R4C8 is the only square in column 8 that can be <9>

R9C8 is the only square in column 8 that can be <3>

Intersection of column 5 with block 5. The value <4> only appears in one or more of squares R4C5, R5C5 and R6C5 of column 5. These squares are the ones that intersect with block 5. Thus, the other (non-intersecting) squares of block 5 cannot contain this value.

R4C6 - removing <4> from <134> leaving <13>

R5C4 - removing <4> from <3469> leaving <369>

R5C6 - removing <4> from <3469> leaving <369>

Intersection of column 4 with block 2. The value <4> only appears in one or more of squares R1C4, R2C4 and R3C4 of column 4. These squares are the ones that intersect with block 2. Thus, the other (non-intersecting) squares of block 2 cannot contain this value.

R2C6 - removing <4> from <1348> leaving <138>

Intersection of column 8 with block 3. The value <4> only appears in one or more of squares R1C8, R2C8 and R3C8 of column 8. These squares are the ones that intersect with block 3. Thus, the other (non-intersecting) squares of block 3 cannot contain this value.

R1C7 - removing <4> from <248> leaving <28>

R2C7 - removing <4> from <48> leaving <8>

R1C7 can only be <2>

R4C7 can only be <4>

R4C5 can only be <1>

R5C9 can only be <3>

R4C9 can only be <2>

R4C6 can only be <3>

R2C6 can only be <1>

R2C8 can only be <4>

R8C6 can only be <4>

R1C4 can only be <4>

R3C4 can only be <9>

R2C4 can only be <3>

R1C8 can only be <1>

R3C5 can only be <8>

R5C4 can only be <6>

R3C2 can only be <1>

R7C5 can only be <9>

R5C6 can only be <9>

R7C4 can only be <1>

R5C5 can only be <4>

R7C8 can only be <2>

R7C9 can only be <8>

R7C6 can only be <6>

R9C9 can only be <4>

R8C9 can only be <1>

R9C6 can only be <8>

R1C2 can only be <8>