Inditex SA (IDEXY)  shares fell in Madrid Wednesday after the world's largest clothing retailer posted slightly weaker-than-expected earnings for the first half of its fiscal year and said global online sales launches were "on track" for the second half.

The Spain-based group, which owns the Zara and Bershka brands, said operating earnings for the six months ending in July came in at €2.29 billion ($2.75 billion), just shy of the FactSet consensus of €2.34 billion but up 9% from the same period last year. Like-for-like sales, the group said, grew 6% while net sales were 11% higher at €11.7 billion.

Gross margins, however, slipped by 1.8 percentage points from the first three months of the year to 56.4% of sales, "mainly due to the mix effect caused by the strong appreciation of the euro versus most major currencies since June", the company said. "Inditex also took the commercial decision to make a quick transition from the Spring/Summer season into Autumn/Winter, programming in a strong launch of the campaign in August."

The euro gained around 8.7% against the U.S. dollar over the May to July period, Initex's second quarter, a move that pressured its cost base and blunted the converted impact of its overseas sales. The euro's gain over the first three month's of the company's fiscal year was only 1.9%.

Inditex shares were marked 2.4% lower in the opening 30 minutes of trading in Madrid and changing hands at €31.88 each, trimming their fiscal year rise (from Feb. 1) to 4.6%, a move that far outpaces the 9.8% decline over the same time period for its main European rival, Sweden's H&M Hennes & Mauritz AB (HNNMY) .

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