My articles link to a lot of sources. Should all external links be nofollow?
Not necessarily. Editorial links to trusted sources you genuinely recommend can be normal follow links. Use rel="sponsored" for paid or affiliate links, rel="ugc" for user-generated links, and nofollow when you don't want to vouch for a site.
Pages with dozens of follow links to commercial sites can look unnatural, so for long lists of companies it is reasonable to use nofollow.
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