New York - ContextWeb, the provider of a contextual online advertising exchange, announced on Tuesday that it has closed a $26 million fourth round of funding, led by Investor Growth Capital.

San Francisco - ON24, a provider of webcasting and virtual events services, announced on Tuesday that it has secured over $8 million in new equity and expansion capital financing.

New York - Panther Express, a provider of digital content delivery network services, announced on Wednesday that it has raised $15.75 million in second round funding, led by Index Ventures.

Andover, Mass. - Pixtronix, a developer of display technology for mobile multimedia devices, has raised $20 million in its second round of venture financing, led by DAG Ventures, PEHub.com reported.