"The lady told us she had taken the notes as an invitation to complete the crossword," as a police spokesman told the Telegraph.
Officials told Hannelore not to lose sleep over writing on the artwork. Gerlinde Knopp, who was in charge of the excursion, also came to Hannelore's defense. Knopp told the BBC that the exhibit had been full of interactive art. Reading-Work-Pieces was unaccompanied by a sign warning visitors not to write in the blanks.
"We will let the lady know that the collector took the damage to the work in good humor, so she doesn't have a sleepless night," museum director Eva Kraus said to the Telegraph. For insurance reasons and because the Neues Museum is state-owned, however, the curators filed a criminal complaint.
Restorers were able to remove the pen marks, restoring the art to its original state. Meanwhile, the investigation into the criminal complaint is ongoing. But the Neues Museum curators said the owner is also approaching the incident with good humor.
Hannelore, however, wants to have the last laugh.
In response to the police investigation, Hannelore has lawyered up. Heinz-Harro Salloch, the attorney representing Hannelore, says that the retired dentist is arguing she not only caused no harm to the art, she "only completed it as the artist intended," according to Deutsche Presse-Agentur.
Ars Technica U.K. reported that her seven-page rebuttal described her pen marks as an "invigorating re-working" that in fact added value to the piece. Furthermore, her additions brought the little-known piece into an international spotlight.
No one could ask Kopcke his thoughts, because the artist died in 1977. But as Ars Technica and others have noted, the artist ascribed to the Fluxus school of art. It held jokey, waggish notions about permanence and ownership, and often involved audience participation.
Hannelore also seems to have embraced that philosophy - as Ars Technica reported, according to her rebuttal she claims a copyright of the newly-invigorated art. She has so increased the value, the rebuttal argues the owner could sue the museum for scrubbing the retired dentist's additions.
When the museum displays Kopcke's Reading-Work-Pieces in the future, a sign will warn visitors not to write on the crossword.