The rise in stock prices sparked talk of building a new factory.
Literal
Stock-price rise [catalyst-を契機に] new-factory construction [possessive-の] talk [subject-が] came-up.
~を契機に ('taking X as a catalyst/trigger') is a formal causal connector — something happens and serves as impetus for what follows. 持ち上がる ('to come up, be raised') is the intransitive partner of 持ち上げる — here, the topic of building a factory 'came up' on its own in response to the stock-price catalyst.