May 16 (Reuters) - Blackbaud ( BLKB ) rejected a

sweetened $4.3 billion takeover offer from Clearlake Capital

Group, saying it significantly undervalued the cloud software

provider.

This is the second time that Blackbaud ( BLKB ) has spurned the

overtures of its largest shareholder, which has been swooping

down on software companies as it bets on demand for

cloud-related services.

The private equity firm made its latest offer last month,

valuing each share of Blackbaud ( BLKB ) at $80, compared with the $71

per share offered in March last year.

Blackbaud ( BLKB ) said in a letter to Clearlake's board on Wednesday

that the firm's "indication of interest significantly

undervalues the company and is not in the best interests of all

Blackbaud ( BLKB ) stockholders."

In March, Blackbaud's ( BLKB ) board terminated its shareholder

rights plan that was adopted in October 2022 to prevent any

entity from acquiring a stake of more than 20%.

Blackbaud ( BLKB ) shares have gained 23% since Clearlake announced

its initial interest in the company in March last year. The PE

firm owns an 18.89% stake in Blackbaud ( BLKB ) according to LSEG data.

Clearlake, along with Francisco Partners, recently agreed to

buy the software integrity (SIG) unit of chip designer Synopsys ( SNPS )

.

It has bought several other companies such as Cornerstone

OnDemand and Quest Software.

Clearlake did not immediately respond to a Reuters request

for comment on Blackbaud's ( BLKB ) rejection.