In Q3'26, Cisco's operating expenses totaled $5.89B USD, with R&D expenses at $2.38B USD and SG&A expenses at $3.52B USD, reflecting a slight quarterly increase from Q2'26's $5.92B USD total driven by modest growth in both categories. Over the period from Q4'23 to Q3'26, total operating expenses exhibited an overall upward trend, rising from $5.22B USD to $5.89B USD, primarily fueled by consistent increases in R&D from $1.95B USD to $2.38B USD and a volatile but net positive trajectory in SG&A from $3.27B USD to $3.52B USD, with notable spikes in Q4'24 and Q1'26 highlighting potential investments in innovation and administrative scaling amid stable quarterly fluctuations.