The SALDO lexicon contains a list of lemmas that are used in Språkbanken's corpora (see column 5 in SALDO). Note, however, that there may appear lemmas in the corpora which are not listed in SALDO (currently it is only possible to the lemmatization of compounds).
If you want to have a list of lemmas in a specific corpus, you can use our statistic files.
NB: only files in "the new format" contain lemmas (baseforms), they have the extension "csv" (files in the old format have the extension "txt").